Choosing a grease trap interceptor for a commercial kitchen means balancing wastewater load, under-sink space, and the material you want between the sink and the drain line. The four units here span listed prices from $49.02 to $535.00, so the buying decision is not just about capacity but about what you are willing to spend and where the interceptor has to live. Pick a unit too small and grease can slip past; pick one that is unnecessarily large and you may be giving up cabinet space.
Quick take
The high-capacity carbon steel interceptor is the strongest option for a sink that sees heavy use. The Express KitchQuip steel unit is a reasonable everyday choice if you want a steel body without going to the top of the price range. The compact stainless steel unit is the lowest listed price in the group and is made for a tighter footprint. The large plastic separator offers more container volume below the steel models.
Listed price comparison
| Product | Listed price | Price bar |
|---|---|---|
| 8lb Commercial Steel Grease Trap Interceptor - 4 GPM, PDI Approved | USD 269.95 | |
| Carbon Steel Grease Trap Interceptor for Restaurant Under Sink Kitchen | NSF | USD 535.00 | |
| Grease Trap Interceptor Stainless Steel For Restaurant Kitchen Wastewater Oil Us | USD 49.02 | |
| 50L Grease Trap Interceptor Oil-water Separator Restaurant Kitchen Under Sink | USD 70.15 |
Decision matrix
| Scenario | Best fit | Why |
|---|---|---|
| High-flow under-sink duty | 30 lb carbon steel interceptor | 30 lb rating and 15 GPM flow rate listed for that size |
| Steel-bodied everyday prep sink | 8 lb Express KitchQuip | 4 GPM flow rate and a PDI-approved label |
| Compact countertop or tight sink cabinet | Compact stainless steel grease trap | Small overall dimensions and the lowest listed price |
| Large-capacity handling without the top price | 50L oil-water separator | 50L capacity in a plastic body at a lower listed price |
Product notes
8lb Commercial Steel Grease Trap Interceptor
The Express KitchQuip steel interceptor is a mid-priced, steel-bodied unit for a prep sink or a bar sink with a repeated but not extreme flow. The 8 lb capacity and 4 GPM flow rate are clearly stated, and the unit carries a PDI-approved label. The listed dimensions of 17 by 11 inches give you a concrete idea of its footprint. The limit to keep in mind is the flow rate: once you are closer to a busy kitchen line, 4 GPM may not keep up with peak discharge. Choose this when you want steel construction and a moderate listed price between the compact stainless unit and the high-capacity carbon steel model.
Carbon Steel Grease Trap Interceptor (30 lb)
The 30 lb carbon steel unit is the high-capacity choice here, with a 30 lb rating and a listed 15 GPM flow rate for that size. The carbon steel body has a corrosion-resistant coating, and the unit comes with no-hub connections, a T-vent, a non-skid deck plate, and removable baffles. That list points to a complete under-sink setup for a busy kitchen. The limitation is the price: this is the highest listed price in the comparison, so it only makes sense if you genuinely need the larger capacity and higher flow. If your sink sees modest use, the smaller steel or plastic units can handle the work for less.
Compact Stainless Steel Grease Trap
The least expensive unit in this set is a stainless steel grease trap with overall dimensions of 35 by 25 by 23 cm. It has four stages of filtration and an automatic shut-off device that stops flow in rain, which is especially useful if the interceptor sits outdoors or in an exposed area. The stainless body makes it a metal option even at the lower end of the price range, and the 1.9-inch wastewater inlet and 0.86-inch grease outlet give you a clear sense of the connection sizes. The trade-off is size: this compact body is not a high-capacity unit, so it is better matched to a small prep sink or a low-volume wastewater stream.
50L Oil-water Separator
The 50L plastic separator is the option to consider when you want a large recovery volume without paying the top price in this set. It is made from PP plastic, has a 50L/13.21gal capacity, and a flow rate of 2.1T/4629.71lbs/h. It also has a 7-layer oil/water separation process and includes a drainage pipe, sealing ring, and assembly accessories. The listed mounting options are freestanding and under countertop, which gives you some placement flexibility. The limitation is material rather than size: if you prefer metal construction, the PP body is not the same as steel. For a kitchen that values container volume over metal, this unit covers a lot of ground.
Final recommendation
Start with the stainless steel compact unit when space is tight and you want the lowest listed price. Choose the large plastic separator when container volume matters more than material. Pick the steel Express KitchQuip interceptor when you need steel construction and moderate flow. If high flow is the deciding factor, the carbon steel interceptor is the strongest choice in this comparison.
