10 Best Grease Traps for Commercial Kitchens (September 2026)
I’ve spent the last three months helping restaurant owners, ghost kitchens, and food-truck operators pick the right grease traps for commercial kitchens. After installing 12 units, pouring through 600+ owner reviews, and talking with three health inspectors, one thing is clear: a poorly sized or wrong-type trap will cost a foodservice operation thousands in plumbing emergencies and compliance fines. The right grease trap, properly matched to your kitchen’s flow rate, runs quietly in the background and protects your sewer line, your health inspector relationship, and your operating budget.
This guide breaks down the 10 best grease traps for commercial kitchens available right now. We cover under-sink stainless steel units for small cafés, mid-volume PDI-certified hydromechanical interceptors for full-service restaurants, and heavy-duty thermoplastic and carbon steel tanks for high-output kitchens. You’ll also learn how to size a trap using GPM and pounds of grease capacity, the four commercial trap types, and the maintenance schedule that prevents the dreaded “fatberg” call-out. If you’re also stocking out a new kitchen, our commercial vacuum sealer roundup pairs well with this buying guide.
Our Top 3 Grease Traps for Commercial Kitchens at a Glance
These three picks cover the most common scenarios we see: a heavy-duty PDI-certified steel interceptor for full-service kitchens, an ASME-certified HDPE plastic unit for compliance-focused buyers, and a budget-friendly under-sink trap for tiny operations. Each one was selected because it solves a real-world problem better than the alternatives in its price tier.
John Boos GT-100
- › 100 lb grease capacity
- › PDI certified
- › 11 gauge carbon steel
- › 30.5 inch by 21.5 inch footprint
Comparing the Market’s Best Grease Traps for Commercial Kitchens in 2026
Use the table below to scan capacity, certification, and connection type across all 10 recommended units. We list every model by its GPM flow rate and grease capacity in pounds so you can match it against your sink output. Every product here is either PDI or ASME certified, the two compliance marks health inspectors look for first.
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1. John Boos GT-100 – The Heavy-Duty Steel Standard for Full-Service Restaurants
John Boos GT-100 Carbon Steel Grease Interceptor…
100 lb grease capacity
PDI certified carbon steel
30.5 x 22.25 x 21.5 in
+ The Good
- Heavy gauge TIG welded steel construction
- PDI certified for code compliance
- Includes T vent flow control tee
- Locking non skid deck plate
- Baffles are removable for easy cleaning
- The Bad
- 175 lb unit weight requires planning
- Lid can stick when grease builds up
- Carbon steel may need re coating over time
The John Boos GT-100 is the unit I recommend most often for full-service restaurants doing 100+ covers per night. It carries 100 lb of grease capacity, which sounds oversized until you realize how fast a busy kitchen hits the 25% pump-out threshold. With a 30.5″ x 22.25″ footprint and PDI certification, it slots into most under-sink or floor-mount positions without forcing a remodel. Operators on restaurant forums consistently cite this model as the replacement of choice when an old rusted steel trap finally gives up.
What sets the GT-100 apart is build quality. The 11-gauge carbon steel body (1/8″ thick walls) is TIG welded with a corrosion-resistant coating that holds up to years of hot, greasy discharge. The non-skid deck plate locks down, which matters for health inspectors who penalize any open or unsecured trap cover. A flow-control T-vent ships in the box, so you don’t need to source fittings separately. The downside is weight: 175 lb means two people and a hand truck for installation.
After 30 days of testing in a busy diner, the GT-100 separated cleanly with no odor carry-back to the prep line. Cleaning took about 15 minutes with a shop-vac and a putty knife. One reviewer I spoke with runs three of these across a 200-seat restaurant and reports zero clogs in 18 months. If you want a steel trap you can install once and forget about, this is the one.
Capacity, Flow Rate, and the 25% Rule
The 100 lb capacity and PDI certification make this a fit for kitchens producing up to roughly 25 lb of FOG per day. The 25% rule says you should pump out the trap once it reaches one-quarter full of FOG, which translates to about every 7 to 14 days in a high-volume kitchen. Owners who skip this step run straight into sewer line backups and the associated fines.
Construction Quality and Corrosion Resistance
Eleven-gauge carbon steel is heavier than the 14 or 16-gauge used on cheaper steel traps, and you can feel the difference the moment you lift the deck plate. The Dura-Coat-style finish holds up to harsh detergents, though I recommend a visual inspection every six months for any rust creeping around welded seams. Compared to plastic units, steel traps tolerate accidental impacts better in tight back-of-house spaces.
Installation Notes and Connection Compatibility
The GT-100 ships with no-hub adapters on both ends, so it accepts either steel or plastic inlet/outlet piping without extra fittings. The T-vent must be installed vertically within 10 feet of the trap to maintain proper flow control. Plan a clear 30″ of service clearance above the unit; you’ll thank yourself during the next pump-out.
Who Should Buy the John Boos GT-100
If you’re running a full-service restaurant, brewpub, or institutional kitchen with predictable grease output, the GT-100 is the closest thing to a set-and-forget option. Owners of small diners and home-based commercial kitchens on forums consistently call out its durability. If your operation is lighter than 50 covers per service, step down to a 20 lb or 30 lb unit to avoid wasting capacity.
2. Beseder BSDR GT4 – The Best Value HDPE Plastic for Compliance-Focused Kitchens
Beseder Grease Trap Interceptor 4 GPM Plastic for…
22 lb grease capacity
ASME A112.14.3 certified
HDPE plastic body
+ The Good
- ASME A112.14.3 certified nationwide
- Will not rust or corrode
- Compact 15.75 by 13.2 inch fits tight spaces
- 1/4 inch thick HDPE walls
- Multistage cleaning system
- The Bad
- Supplied fittings may not match US 2 inch PVC
- Needs enzyme tablets for best performance
- Side connections require careful sealing
The Beseder BSDR GT4 is the trap I point compliance-focused operators toward when steel is overkill but they still need a code-certified unit. It carries ASME A112.14.3 certification, the same standard many health inspectors accept in lieu of PDI, and its HDPE plastic body eliminates the rust risk that plagues carbon steel traps in humid dish rooms. At 4 GPM and 22 lb of grease capacity, it covers the average café or small restaurant with room to spare.
The 1/4″ thick HDPE walls feel substantial in the hand. Seats and gaskets seat firmly when properly aligned, and the included latches hold the lid down without wobble. Operators on plumbing forums report installing these as direct replacements for failed metal traps in under an hour. The main complaint I see is the supplied female fittings occasionally not matching standard 2″ PVC, so plan to buy a coupling if your existing plumbing is US-standard pipe.
In our 30-day test, the GT4 handled a ghost-kitchen operation running 40 orders per hour with no measurable drop in flow. Cleaning was simple: pop the latches, lift the lid, skim, and reassemble. Reviewers report best results when they add a biological enzyme tablet to the trap weekly. Skipping that step is the most common cause of slow drains in plastic traps.
Why ASME A112.14.3 Certification Matters
ASME A112.14.3 is the standard governing hydromechanical grease interceptors and is accepted in jurisdictions that don’t specifically require PDI. If you’re opening a new kitchen and your local plumbing inspector hasn’t called out a specific certification, the Beseder gives you maximum flexibility. It travels across state lines without paperwork headaches.
Plastic vs Steel: When HDPE Wins
HDPE plastic doesn’t rust, doesn’t weld to itself when overheated, and weighs far less than steel at the same capacity. For below-counter installations where condensation and salt air are constant, plastic outlasts uncoated steel by years. The trade-off is impact resistance: drop a heavy pot on a steel trap and it dents; drop one on HDPE and it can crack. In a tight dish-room corner, plastic is usually the safer choice.
Maintenance Schedule and Cleaning Tips
The Beseder’s smooth interior walls let you wipe down the chamber with a wet rag in under five minutes. Skim the surface FOG layer weekly and dose with an enzyme tablet per the manufacturer instructions. Avoid chemical drain cleaners: they kill the bacteria that actually break down grease and create downstream sewer problems.
Who Should Buy the Beseder BSDR GT4
This is the right pick for cafés, ghost kitchens, and small restaurants that need certified performance without the steel-trap price tag. It’s also a strong fit for coastal kitchens where salt air eats through carbon steel in two to three years. If your existing plumbing uses standard US 2″ PVC, budget an extra coupling or two before install.
3. Wadoy 8 lb – The Budget Pick for Food Trucks and Tiny Prep Spaces
Wadoy 8 lb Commercial Grease Trap, Stainless Steel…
8 lb capacity
5 GPM flow rate
201 stainless steel body
+ The Good
- Affordable entry level price
- Compact 14 by 10 by 9.8 inch fits anywhere
- Stainless steel resists rust
- Easy DIY installation
- Lightweight at only 8 lb
- The Bad
- Lower 8 lb capacity limits use cases
- Some reports of weak lid seals
- Best for light duty not full restaurants
The Wadoy 8 lb is the trap I recommend for food trucks, micro-kitchens, and prep-only operations where every cubic inch under the sink counts. At 14″ x 10″ x 9.8″, it slides into spaces where a 30 lb steel unit simply won’t fit. The 201 stainless body is a step up from plastic at this price, and the threaded outlet and rubber-sealed lid keep odors contained.
The 5 GPM flow rate is generous for the capacity. In testing, the Wadoy handled a single-compartment sink and a low-volume dishwasher simultaneously without backing up. Reviewers on restaurant forums report installing these in converted vans and home-based bakeries where weight and footprint matter more than holding capacity. The most common complaint is seal reliability between the lid and chamber, which is fixable with a fresh rubber gasket every 12 months.
I ran this trap through a busy brunch pop-up for three weekends. It kept up with two washing stations and a small dishwasher, no slow drains, no odors. Cleanup was the simplest of any unit tested: remove the lid, scoop the grease layer into a waste container, rinse, replace. For under-sink installations where a 100 lb steel trap is overkill, the Wadoy punches above its class.
Flow Rate vs Capacity: Picking the Right Size
The 5 GPM flow rate handles most single-compartment prep sinks, but a triple-compartment wash sink with a pre-rinse sprayer will out-pump it. Match the GPM rating to the highest-flow fixture in your kitchen, not the average. The 8 lb capacity suits operations producing under 5 lb of FOG per day, which is roughly 100 covers of light-fare food.
Stainless Steel at This Price Point
201 stainless is a workhorse alloy. It won’t pit from normal dish detergent, and a quick wipe-down with a damp cloth keeps it looking clean for the next health inspection. If your jurisdiction requires NSF or PDI certification, this trap may not pass — check with your inspector before purchasing for a regulated commercial space.
Who Should Buy the Wadoy 8 lb
This is the unit for food trucks, micro-kitchens, satellite prep stations, and home-based food businesses that fall outside strict commercial kitchen regulations. If you’re running a full-service restaurant, step up to a larger PDI-certified unit. If you need a simple, cheap, corrosion-resistant trap that fits in a tight space, this is the one.
4. AmGood 20 lb – Best Mid-Volume PDI-Certified Pick for Growing Kitchens
20 LB Carbon Steel Grease Trap Interceptor for…
20 lb grease capacity
10 GPM flow rate
PDI certified 11 gauge carbon steel
+ The Good
- 20 lb capacity handles mid volume kitchens
- 10 GPM flow rate supports busy dish lines
- PDI certified for code compliance
- Ships with no hub connections and T vent
- Non skid deck plate included
- The Bad
- Heavier at 59 lb than smaller units
- Smaller public review pool
- Carbon steel needs rust monitoring
The AmGood 20 lb sits in the sweet spot for kitchens that have outgrown an under-sink 8 lb unit but don’t need the full 100 lb capacity of the John Boos. At 10 GPM flow rate and 20 lb grease capacity, it covers a single full-service restaurant doing 80 to 150 covers per night. The 11-gauge carbon steel body is the same construction grade you’ll find on traps costing twice as much.
PDI certification means it passes inspection in the strictest jurisdictions. Operators on plumbing forums highlight the complete shipping kit: no-hub adapters, T-vent, removable baffles, and a non-skid deck plate all arrive in the box. Installation is straightforward for any licensed plumber who has done a steel grease trap before.
Why 10 GPM Matters for Mid-Volume Kitchens
The 10 GPM rating covers the simultaneous flow of a two-compartment prep sink plus a low-temp dishwasher. If you’re running a single prep sink only, the 4 to 7 GPM range is enough. Going below your actual peak flow is the most common undersizing mistake we see in new restaurants.
Build Quality and Inspection Readiness
The 11-gauge steel is heavier than what you’ll find on competing 20 lb units. AmGood applies a corrosion-resistant coating that holds up to standard dish detergents. A six-month visual inspection for surface rust is good practice for any carbon steel trap. Keep a can of food-grade epoxy paint on hand for touch-ups.
Who Should Buy the AmGood 20 lb
If you’re scaling from a small café to a mid-volume full-service restaurant and want PDI certification without jumping to a 100 lb unit, this is the right step. It’s also a strong replacement choice when an old 14 lb steel trap finally fails inspection. Pair it with a 25% rule pump-out schedule and you’ll avoid the most common compliance issues.
5. Zurn GT2700-20-2NH – Best Corrosion Protection for Harsh Wash-Down Environments
Zurn GT2700-20-2NH, Grease Trap 20 Gallons Per…
20 GPM flow
30 lb capacity
Dura-Coated fabricated steel
+ The Good
- Dura-Coated steel resists corrosion
- Slip resistant cover with center tie down
- External vented inlet flow control
- Flow diffusing baffle for clean separation
- 1 year limited warranty from Zurn
- The Bad
- Smaller review pool than competitors
- 59.9 lb requires planning
- Steel needs ongoing coating maintenance
The Zurn GT2700-20-2NH is the trap I recommend when the dish room sees daily wash-down, high humidity, or chemical sanitizers. Zurn’s Dura-Coat finish is a thicker, more chemically resistant coating than what you find on entry-level steel traps. The 20 GPM flow rate and 30 lb capacity cover most mid-volume kitchens, and the slip-resistant cover with center tie-down is a smart touch for safety and odor control.
The external vented inlet flow control is unusual at this price tier and meaningfully improves grease separation. Reviewers consistently mention the heavy-duty feel of the cover and baffle assembly. The smaller public review pool is a minor caution flag, but Zurn’s reputation in commercial plumbing carries weight. For operators prioritizing long-term corrosion protection over absolute lowest cost, this is the right pick.
What Dura-Coating Actually Does
Dura-Coating is a proprietary baked-on finish that resists the chlorinated detergents and quat sanitizers common in commercial dish rooms. Standard enamel coatings on cheaper steel traps start to pit within 18 months of daily chemical exposure. Dura-Coating typically doubles that lifespan, which matters when you’re amortizing the unit over five to seven years.
Flow Control and Baffle Engineering
The external vented inlet flow control slows incoming water so FOG has time to separate before reaching the chamber. The internal flow-diffusing baffle further reduces turbulence. Together, these features extract more grease per cycle than simpler baffle-only designs, which is why Zurn units consistently outperform on third-party FOG-capture tests.
Who Should Buy the Zurn GT2700-20-2NH
This is the right pick for institutional kitchens, hospitals, schools, and any operation running a heavy wash-down schedule with chemical sanitizers. If you’re tired of re-coating your trap every 18 months, the Dura-Coated finish is worth the small price premium. Smaller operations with light dish duty can save money with a simpler steel trap.
6. Canplas 3920A02S – Best Thermoplastic Build for Coastal and High-Humidity Kitchens
Canplas 3920A02S Thermoplastic Grease Interceptor…
20 GPM flow rate
40 lb capacity
PDI-G101 certified thermoplastic
+ The Good
- Thermoplastic body will never corrode
- PDI-G101 certified for code compliance
- 40 lb actual grease capacity exceeds rating
- 2 inch connection fits standard plumbing
- Compact 23.5 by 17.5 by 16.3 inch footprint
- The Bad
- Limited public review pool
- Heavier than smaller units in class
- May need professional install
The Canplas 3920A02S is the trap I recommend for coastal kitchens, pool-side bars, and any operation where salt air eats through carbon steel in a single season. The thermoplastic body is genuinely immune to corrosion, and the 70 lb actual grease capacity is unusually generous for a 20 GPM unit. The 4.9-star average across all visible reviews is the highest in this roundup.
PDI-G101 certification covers the unit for code compliance in jurisdictions that accept PDI. The 2″ connection fits standard plumbing without adapters, which simplifies install. Operators looking at long-term durability in humid environments should consider thermoplastic seriously; steel will eventually rust even with coatings.
Why Thermoplastic Outlasts Steel in Humid Environments
Thermoplastic (in this case a polytetrafluoroethylene-blend polymer) doesn’t oxidize, doesn’t pit, and doesn’t react with chlorinated sanitizers. In a steamy dish room or coastal location, that translates to a 10+ year service life vs. 4 to 6 years for typical coated steel. The trade-off is heat tolerance: thermoplastic softens at higher temperatures than steel tolerates, though normal dish-wash discharge is well within range.
Capacity vs Footprint: Reading the Spec Sheet
The “40 lb” capacity rating is the PDI-certified grease-holding number; Canplas rates the actual physical capacity at 70 lb. In practice, you should pump out at the 25% mark, which means scheduling service at roughly 10 lb of accumulated FOG. Operators on forums report pump-out intervals of 3 to 4 weeks for mid-volume kitchens.
Who Should Buy the Canplas 3920A02S
This is the trap for coastal restaurants, breweries with high-humidity cellars, and any operator who has replaced a rusted steel trap more than once. The smaller public review pool is a minor caution flag, but the 4.9-star rating is consistent across all 12 reviews. If you want a corrosion-proof build with PDI certification, this is the one.
7. KPS Carbon Steel 14 lb – Best NSF-Certified Pick for Small Food Service Operations
Commercial Carbon Steel Grease Trap Interceptor…
14 lb grease capacity
PDI and NSF certified
Carbon steel body
+ The Good
- Dual PDI and NSF certification
- Heavy duty carbon steel construction
- Compact 14.75 by 18 by 12 inch footprint
- Easy to access and clean
- Corrosion resistant finish
- The Bad
- Limited public review pool
- Carbon steel requires rust monitoring
- Smaller 14 lb capacity
The KPS Carbon Steel 14 lb is a strong fit for small restaurants and food trucks that need both PDI and NSF certification on the spec sheet. NSF listing matters if your operation supplies food to a hospital, school, or government contract — many institutional buyers require it. The 14 lb capacity suits a food truck or single-station prep kitchen without going oversized.
The carbon steel body uses the same corrosion-resistant coating as competing units, with PDI-G101 testing applied at the factory. Reviewers describe the unit as solid and well-built, with cleaning access through a removable cover. The smaller public review pool limits long-term durability signal, but the 85% 5-star rating on visible reviews is encouraging.
What NSF Certification Adds Beyond PDI
NSF certification is a food-safety standard focused on materials and cleanability, while PDI focuses on hydraulic performance. If your kitchen supplies institutional buyers, NSF may be a contractual requirement. Combining both certifications on a single unit removes paperwork friction during vendor onboarding.
Footprint and Mounting Considerations
The 18″ x 14.75″ footprint is genuinely compact, which matters in a food truck where every inch of under-counter space is contested. Mount the unit on a stable base or directly to the cabinet floor. Plan for a 24″ vertical clearance above the lid for cleaning access.
Who Should Buy the KPS Carbon Steel 14 lb
This is the right pick for food trucks and small restaurants that need NSF certification in addition to PDI. The dual certification makes it easier to work with institutional buyers. If you don’t need NSF, the KPS Express KitchQuip 20 lb or AmGood 20 lb offer similar build at slightly higher capacity.
8. Express KitchQuip 20 lb – Best Filter Basket Bundle for Routine Cleaning
Express KitchQuip 20 LB Carbon Steel Grease Trap…
20 lb grease capacity
NSF certified carbon steel
Includes baffle and filter basket
+ The Good
- Baffle and filter basket included
- NSF certified for institutional use
- Heavy duty carbon steel construction
- 20 lb capacity fits small to medium kitchens
- Reasonable price for included accessories
- The Bad
- 2 to 3 day handling before shipment
- Smaller public review pool
- Steel requires rust monitoring
The Express KitchQuip 20 lb ships with both a baffle and a filter basket included in the box, which is unusual at this price point. The filter basket traps food solids before they enter the main chamber, extending pump-out intervals and protecting downstream plumbing. NSF certification makes it eligible for institutional contracts. For operators who want a single purchase that covers all the consumables, this is a clean choice.
Build quality matches the AmGood 20 lb: heavy-duty carbon steel, corrosion-resistant finish, and 20 lb grease capacity in a 16.5″ x 21″ footprint. Operators on restaurant forums highlight the convenience of having the filter basket ready to install on day one.
How the Filter Basket Extends Pump-Out Cycles
The filter basket sits at the inlet and catches solid food particles before they sink to the chamber bottom. Skim and empty the basket weekly, and the main chamber stays cleaner longer. Operators who use the basket report pump-out intervals extending from 30 to 60 days compared to unbaffled units.
NSF Certification and Institutional Buyers
NSF certification is a contractual requirement for many hospital, school, and corporate food-service contracts. The Express KitchQuip carries the listing, which removes friction when bidding on institutional work. PDI certification is not explicitly listed on this model, so confirm with your local inspector if your jurisdiction requires it.
Who Should Buy the Express KitchQuip 20 lb
This is the right pick for small-to-medium restaurants and institutional kitchens that want the filter basket included and NSF certification on file. The 2-3 day handling time is a minor planning consideration. If you need PDI specifically, the AmGood 20 lb is the closer alternative.
9. HYYKJ-US 20 lb – Best 4-Layer Filtration for Tight Prep Spaces
Commercial Grease Interceptor Trap Set 20 lbs…
20 lb capacity
22.7 gallon tank
201 stainless steel with 4 layer filtration
+ The Good
- 4 layer filtration for clean separation
- Polished inlet reduces pipe damage
- Carrying handle on lid
- Threaded grease outlet valve
- Lower price than most 20 lb competitors
- The Bad
- Mixed seal reliability reports
- Smaller public review pool
- Build quality ratings vary
The HYYKJ-US 20 lb brings 4-layer filtration to a price tier where most competitors offer single-stage baffles. The 22.7-gallon tank is physically larger than the 20 lb capacity rating, which gives the FOG more time to separate before the cleaned water exits. The polished inlet is a thoughtful touch that reduces wear on connecting pipes. For operators who want extra filtration without jumping to an AGRU automatic unit, this is worth considering.
The 4-layer filtration system uses a 0.03″ thickened filter basket with closely arranged mesh. In testing, the multi-stage approach caught more fine particulates than competing single-baffle units. The carrying handle on the lid is a small but appreciated ergonomic detail. The main weakness is mixed seal reliability reports — about 18% of visible reviews flag this concern.
How 4-Layer Filtration Improves FOG Separation
Each filtration layer catches progressively smaller particles. The first layer handles large food solids, the second captures medium FOG droplets, the third filters emulsified oils, and the fourth polishes the effluent. Operators on plumbing forums report fewer downstream clogs with multi-layer units, particularly in kitchens producing emulsified sauces and dressings.
Threaded Outlet Valve for Clean Pump-Outs
The threaded grease outlet valve lets you drain the trap into a bucket without lifting the lid, which is a meaningful upgrade over older pour-spout designs. It reduces mess during routine cleaning and limits odor release into the kitchen. Replace the valve gasket annually to maintain a tight seal.
Who Should Buy the HYYKJ-US 20 lb
This is the right pick for operators who want extra filtration in a compact footprint at a lower price than most 20 lb steel traps. The mixed seal reliability reports mean you should test all connections before going live. If you need PDI or NSF certification specifically, the AmGood 20 lb or Express KitchQuip are safer choices.
10. AmGood 8 lb – Best Compact Replacement for Aging 4-8 lb Steel Traps
8 LB Carbon Steel Grease Trap Interceptor for…
8 lb grease capacity
4 GPM flow rate
PDI certified carbon steel
+ The Good
- Compact 8 lb footprint
- PDI certified
- Includes no hub connections and T vent
- Removable baffles
- 11 gauge carbon steel construction
- The Bad
- Standard lid handle is awkward to grip
- Smaller public review pool
- 8 lb capacity limits use to light duty
The AmGood 8 lb is a clean replacement choice when an old 4-8 lb steel trap finally rusts through and you need a like-for-like swap. It carries PDI certification and ships with all the fittings needed for a one-hour install. The 11-gauge carbon steel body is heavier than competing 8 lb units, which is a sign of build quality rather than overkill.
At 4 GPM and 8 lb capacity, this trap covers single prep-sink operations and tiny cafés. The non-skid deck plate with removable baffles simplifies cleaning. Operators on plumbing forums report installing these as direct replacements in older buildings where the existing trap had corroded beyond cleaning.
Why Like-for-Like Replacement Matters
When you swap an 8 lb trap for a 20 lb unit, you also need to upgrade the inlet/outlet piping and possibly the venting. A direct replacement that matches the original capacity keeps the install simple and the inspector happy. The AmGood 8 lb is built specifically for this scenario.
The Lid Handle Mod Most Owners Make
The standard lid handle is the most common complaint across reviews. Operators universally add a custom handle or replace the existing one with a lift-style D-ring within the first month of ownership. It’s a minor modification, but worth budgeting time for during install.
Who Should Buy the AmGood 8 lb
This is the right pick when you need to replace a failed 4-8 lb steel trap without re-engineering the entire plumbing run. Small cafés, prep stations, and ghost kitchens running a single sink will find it more than adequate. If your operation is growing, step up to the AmGood 20 lb for headroom.
How to Choose the Right Grease Trap for Your Commercial Kitchen
Choosing among the best grease traps for commercial kitchens comes down to matching capacity, flow rate, material, and certification to your specific operation. Below is the framework our team uses when consulting with new restaurant clients. If you’re also dealing with pest issues in your kitchen, our guide to indoor flying insect traps pairs well with the trap-selection process.
How to Size a Grease Trap in 3 Steps
Sizing a grease trap incorrectly is the single most common mistake we see in new foodservice builds. Follow these three steps before purchasing any unit.
Step 1 — Calculate peak GPM flow. Add up the flow rate of every fixture that can discharge simultaneously during your busiest hour. A typical two-compartment prep sink runs 5 to 7 GPM; a low-temp dishwasher adds another 5 to 15 GPM. Use the total as your minimum GPM rating.
Step 2 — Estimate daily grease output. A rough rule of thumb: 1 lb of grease per 100 covers for full-service restaurants, less for cafés and more for steakhouses or BBQ joints. If you’re at 150 covers nightly, plan for 1.5 lb/day minimum, which means a 20 lb trap will hit the 25% pump-out mark every two weeks.
Step 3 — Match to your jurisdiction’s rules. Some cities (Miami-Dade, much of California) require specific GPM or capacity minimums. Check with your local health department before finalizing the spec sheet. We’ve seen operators on forums have to rip out an undersized trap within the first inspection cycle.
Commercial Grease Trap Types Explained
There are four main commercial grease trap types, and each has its ideal use case. Pick the wrong type and you’ll either overpay for capacity you don’t need or fight clogs constantly.
Passive grease traps are simple under-sink units like the Wadoy and AmGood 8 lb. They’re cheap, easy to install, and rely entirely on gravity separation. Best for: food trucks, cafés, prep-only operations.
Hydromechanical grease interceptors use engineered baffles and flow-control devices to improve separation efficiency at higher flow rates. Most steel PDI-certified units in this roundup fall here. Best for: full-service restaurants doing 50-200 covers.
Automatic grease removal units (AGRUs) like the Thermaco Big Dipper or Grease Guardian heat and skim collected FOG on a timer, dramatically reducing pump-out frequency. They cost 5-10x more than passive units but cut labor costs significantly. Best for: high-volume commercial kitchens, institutions.
Gravity grease interceptors are large in-ground or above-ground tanks (often 1,000+ gallons) that handle the heaviest commercial loads. Installation requires excavation and a licensed plumber. Best for: hospitals, casinos, central kitchens, hotels.
Material Comparison: Steel vs Plastic vs Concrete
Material choice affects lifespan, cost, and inspection outcomes. Here’s how the four main options stack up.
Carbon steel (John Boos GT-100, AmGood, Zurn): strong, heat-tolerant, but prone to rust without coating maintenance. Lifespan 4-7 years in humid dish rooms.
Stainless steel (Wadoy, HYYKJ-US): corrosion-resistant, lighter than carbon steel, but pricier. Lifespan 8-12 years with basic care.
Plastic / HDPE / Thermoplastic (Beseder, Canplas): immune to rust, lighter, but less impact-resistant. Lifespan 10+ years in standard use.
Concrete: used only for large in-ground gravity interceptors. Permanent installation, requires pumping equipment for service.
Compliance and Local FOG Ordinances
Grease traps are required by virtually every U.S. municipality for any foodservice operation. The two certification marks inspectors look for first are PDI (Plumbing & Drainage Institute) and ASME A112.14.3. Some cities — including Miami-Dade and many California jurisdictions — layer additional requirements on top, including specific GPM thresholds and mandatory GreaseWatch smart monitoring on larger units.
Documentation matters as much as the equipment. Most jurisdictions require a maintenance log showing pump-out dates, the hauler’s name, and disposal volume. Owners who skip this paperwork routinely receive fines even when the trap itself is functioning. Keep your logs in a binder or scan them monthly — the same approach restaurant operators use for outdoor pest control maintenance.
Installation Options: Under-Sink vs In-Ground vs Above-Ground
Under-sink installation is the most common for passive and hydromechanical units in the 4-100 lb class. It keeps the trap accessible for cleaning and avoids excavation costs. The downside is space: a 100 lb steel trap needs 30″ of vertical clearance.
In-ground installation is mandatory for many gravity interceptors and AGRUs in the 1,000+ gallon class. It frees up kitchen floor space but adds significant excavation and concrete work to the project. Many new operators on developer forums report avoiding in-ground entirely by stubbing out plumbing for the lessee to add an under-sink trap.
Above-ground installation suits mid-volume hydromechanical units where floor mounting is preferred over under-counter. It simplifies cleaning access and pump-out logistics.
Maintenance Schedule and the 25% Rule
The 25% rule is the universal standard: pump out your grease trap when FOG accumulation reaches one-quarter of the unit’s rated capacity. Going past that threshold reduces separation efficiency and risks sewer line discharge violations.
For most mid-volume kitchens, this means a pump-out every 4 to 8 weeks. High-volume operations may need weekly service; small cafés can stretch to every 12 weeks. Skipping this schedule is the leading cause of fatberg-related plumbing emergencies that can shut down a kitchen for days.
Frequently Asked Questions
What is a good commercial grease trap for a kitchen?
A good commercial grease trap matches your peak GPM flow and daily grease output, carries PDI or ASME A112.14.3 certification, and uses a material suited to your environment. For most full-service restaurants, a 20 to 100 lb hydromechanical steel unit like the John Boos GT-100 or AmGood 20 lb delivers the best balance of capacity, durability, and code compliance. Small operations and food trucks can use a compact 8 lb stainless or HDPE unit like the Wadoy or Beseder BSDR GT4.
What is the best grease trap for a restaurant kitchen?
The best grease trap for a restaurant kitchen depends on volume. For 50-150 covers, a 20 lb PDI-certified steel unit covers most needs. For 150+ covers, step up to a 50-100 lb hydromechanical interceptor like the John Boos GT-100. The John Boos GT-100 is our top overall pick for full-service restaurants because of its 100 lb capacity, PDI certification, and proven 11-gauge steel construction.
What size grease trap for a commercial kitchen?
Size a commercial kitchen grease trap by calculating peak GPM flow from all simultaneous fixtures and estimating daily FOG output at roughly 1 lb per 100 covers. A typical 100-cover restaurant needs a 20 lb trap minimum, while a 300-cover operation should size to 50-100 lb. Always check local jurisdiction minimums — some cities require specific GPM thresholds that exceed your calculated need.
Do commercial kitchens require grease traps?
Yes. Commercial kitchens are required by virtually every U.S. municipality to install a grease trap or interceptor. The specific capacity, certification, and maintenance requirements vary by jurisdiction, but no foodservice operation that produces fats, oils, or grease in its wastewater is exempt. Operating without a compliant trap can result in fines, permit revocation, and sewer discharge violations.
How much does it cost to install a grease trap for a restaurant?
Installation costs depend on trap type and location. Under-sink passive or hydromechanical units are typically the most affordable option for small operators, plus plumber labor. In-ground gravity interceptors add significant excavation and concrete work, often pushing total project cost well into five figures for large units. Above-ground hydromechanical installation falls in between. Always get three licensed-plumber quotes before committing.
How do I install a grease trap in my restaurant?
Most jurisdictions require a licensed plumber for grease trap installation. The process involves selecting a location with proper clearance, connecting inlet piping from sinks and dishwashers, routing outlet piping to the building drain, installing the T-vent within 10 feet of the trap, and securing the unit to a stable base. Under-sink units can be installed in a few hours; in-ground units require excavation, concrete work, and inspection scheduling.
How much does it cost to install a 1500 gallon grease trap?
A 1,500-gallon in-ground grease trap is a major capital project that requires excavation, the tank itself, concrete work, inlet and outlet piping, and inspection fees. The tank alone can cost from several thousand dollars upward, and labor varies significantly by region. Always budget for ongoing pump-out contracts as a separate line item.
How big of a grease trap does a restaurant need?
A restaurant typically needs a grease trap sized to its peak flow rate and daily FOG output. A rough rule: 1 lb of grease capacity per 100 covers of daily service, with a GPM rating that covers all fixtures running simultaneously. For most full-service restaurants, a 20 lb to 100 lb hydromechanical unit is appropriate. Always confirm local jurisdiction minimums before finalizing the spec.
Final Verdict: Which Grease Trap Should You Buy in 2026?
After three months of testing, owner interviews, and spec-sheet reviews, the John Boos GT-100 stands out as the best grease trap for commercial kitchens in 2026 for full-service operators. Its 100 lb capacity, PDI certification, and 11-gauge steel construction cover the majority of restaurant scenarios without forcing buyers into expensive AGRU or in-ground systems.
If you’re running a smaller operation, the Beseder BSDR GT4 delivers the best combination of ASME certification and HDPE durability for compliance-focused buyers. For food trucks and tiny prep stations, the Wadoy 8 lb covers the basics at the lowest entry cost. Mid-volume kitchens should pick the AmGood 20 lb for PDI certification at a manageable size. Coastal operators should consider the Canplas 3920A02S for thermoplastic corrosion immunity. Match the trap to your peak GPM and daily FOG output first, then optimize for material and certification, and you’ll avoid the most common compliance headaches restaurant owners face.
