Terminology Guide

Grease Trap vs. Grease Interceptor: What Los Angeles Restaurants Need to Know

Understanding the difference, why the terms are often used interchangeably, and what your restaurant actually needs.

LA Restaurant Services · Field Technician Notes

The simple answer

"Grease trap" usually refers to a small under-sink or compact unit (10–100 gallons).

"Grease interceptor" usually refers to a larger unit (250+ gallons) installed outdoors or in a utility space.

But both do the same thing: trap grease before it enters the city sewer. In Los Angeles County regulations, they are all classified as "grease interceptors." Field technicians often use the terms interchangeably, and there is no strict legal difference — it is mostly a matter of size and common usage.

Side-by-side comparison

Factor	Grease Trap	Grease Interceptor
Size	10–100 gallons (under-sink or small indoor)	250 gallons to 2,000+ gallons (outdoor or large indoor)
Installation	Typically under a sink or in a small indoor floor pit	Usually installed outdoors or in a larger indoor/basement pit connected to main sewer
Designed for	Small prep operations, coffee shops, light fryers	Full-service restaurants, commissaries, high-volume kitchens, catering
Maintenance interval	Weekly to bi-weekly for high-use kitchens	Every 4–12 weeks depending on size and volume
Cost per service	$75–$150 per pumping	$250–$800+ depending on size and accessibility

Why they work the same way

Both devices use gravity separation to trap FOG, but they differ in size and capacity. To understand what happens when either reaches capacity, see what causes restaurant kitchen drain backups. For high-volume drains, commercial hydro jetting may complement regular pumping.

Both use the same basic principle

A grease trap and a grease interceptor both work by gravity separation. Grease floats to the top, solids sink to the bottom, and cleaner water exits the outlet. The difference is scale and capacity, not function.

The LACDPH calls large ones "interceptors"

In Los Angeles County regulations, grease traps and grease interceptors are technically the same device — they are all classified as "grease interceptors" in the code. Field technicians and restaurant operators often use both terms interchangeably, but they refer to the same type of equipment.

Both require regular maintenance and documentation

Whether you have a small under-sink trap or a 2,000-gallon outdoor interceptor, you need the same thing: predictable service, waste manifests, and compliance records. The maintenance schedule differs, but the documentation requirement is identical.

What to ask when scheduling service

Whether you call it a grease trap or grease interceptor, the questions you need to answer are the same:

1.How large is your unit? (10 gal, 50 gal, 500 gal, 1000 gal?)
2.Where is it located? (under sink, outdoor pit, basement, etc.?)
3.When was it last serviced?
4.How often should it be serviced based on your kitchen volume?

Not sure what you have?

We can assess your current setup and recommend the right grease trap or interceptor service schedule for your kitchen.

Request Assessment