Grease Trap vs Grease Interceptor: What's the Difference?

Both devices do the same fundamental job: slow wastewater down so fats, oils and grease separate and stay out of the sewer. The words are used interchangeably in conversation, and both are technically correct. In the field, though, they usually describe different equipment.

Grease trap — usually the smaller unit

Typically a compact unit inside the kitchen, under a sink or dishwasher, or set into the floor nearby. Capacity is modest, servicing is frequent, and access is through the kitchen. Because volume is small, a busy kitchen can fill one in weeks.

Grease interceptor — usually the larger in-ground tank

A much larger tank, generally in-ground and outside the building, sized for the whole kitchen's flow. Access is through lids in a lot, loading area or grounds. Servicing is done with a vacuum truck and takes longer, but intervals are usually longer too.

Why the distinction matters to you

• Servicing method: hand-serviceable small trap versus vacuum pump-out of a large tank
• Interval: small traps need frequent attention; interceptors are easier to forget for too long
• Access planning: kitchen route versus lot or drive-lane setup
• Cost drivers: volume removed and access, both of which differ significantly
• Risk profile: an overflowing kitchen trap is messy; a blocked in-ground interceptor stops the kitchen

Many kitchens have both

It is common to find small traps on specific fixtures plus a main in-ground interceptor. Both need to be on the schedule — servicing one and ignoring the other still ends in a backup.

If you are not sure what you have, tell us the facility type and where the access lids are and we can usually identify it before attending.