How often should a grease trap be cleaned?

There is no fixed interval in New York City. DEP requires that every interceptor be cleaned as frequently as necessary to avoid exceeding its rated capacity. In practice most operators clean monthly to quarterly, but the correct answer depends on your unit size and how much grease your kitchen actually produces.

What is the 25 percent rule?

An operating convention from the wider FOG industry: clean before grease and solids reach a quarter of the unit’s liquid depth. It is a practical way to satisfy DEP’s "before rated capacity" wording, not itself a DEP rule. Treat it as a trigger, not a legal standard.

What does it cost to get this wrong?

DEP states the maximum penalty for not complying with the sewer use rules is currently $10,000 per day, per violation, verified 2 September 2026. The bigger practical cost is usually a backed-up line during service.

What if my interceptor is too small?

DEP inspectors can order the owner or operator to install a properly sized unit based on the Building Code and Sewer Use Regulations. Undersizing is not a way to reduce cleaning cost; it increases both frequency and exposure.

← NYC compliance

There is no fixed schedule for cleaning a grease trap

Most guides will tell you every one to three months. New York does not say that. DEP requires every interceptor to be cleaned as frequently as necessary to avoid exceeding its rated capacity, which means the right interval depends on your unit and your kitchen, not on a calendar.

The number that should focus the mind

DEP states the maximum penalty for not complying with the sewer use rules is currently $10,000 per day, per violation, as of 2026-09-02.

So how do I work out my interval?

The working standard across the industry is the 25 percent rule: clean before grease and solids reach a quarter of the unit’s liquid depth. That is a practical way to stay inside DEP’s wording rather than a rule DEP itself publishes, and it is worth knowing the difference if an inspector ever asks.

Measure at the interval you are on now. If you are hitting a quarter depth early, shorten it. If the trap is barely loaded, you are paying for pumping you do not need. Four things move the number:

Covers or fry stations

A high-volume fryer line loads a trap faster than a sandwich counter with the same seat count.

Interceptor size

An undersized unit fills faster and is also its own violation. DEP inspectors can order a correctly sized replacement.

What you cook

Wok, grill and fryer kitchens generate far more FOG than bakeries or salad-forward menus.

Dishwashing method

Pre-rinse habits and chemical sanitizers change how much grease reaches the trap at all.

Does my business need an interceptor?

DEP says every business that disposes of grease, fats or oil should have one, and names these among others:

Restaurants and cafeterias
Clubs and catering halls
Butcher shops and slaughterhouses
Fish markets
Supermarket food processing areas
Delicatessens

Installation is not a DIY job either. DEP requires that only licensed plumbers install grease interceptors, and an undersized unit is its own violation: inspectors can order a correctly sized replacement based on the Building Code and Sewer Use Regulations.

Common questions

How often should a grease trap be cleaned?: There is no fixed interval in New York City. DEP requires that every interceptor be cleaned as frequently as necessary to avoid exceeding its rated capacity. In practice most operators clean monthly to quarterly, but the correct answer depends on your unit size and how much grease your kitchen actually produces.
What is the 25 percent rule?: An operating convention from the wider FOG industry: clean before grease and solids reach a quarter of the unit’s liquid depth. It is a practical way to satisfy DEP’s "before rated capacity" wording, not itself a DEP rule. Treat it as a trigger, not a legal standard.
What does it cost to get this wrong?: DEP states the maximum penalty for not complying with the sewer use rules is currently $10,000 per day, per violation, verified 2 September 2026. The bigger practical cost is usually a backed-up line during service.
Can I install the interceptor myself?: No. DEP requires that only licensed plumbers install grease interceptors.
What if my interceptor is too small?: DEP inspectors can order the owner or operator to install a properly sized unit based on the Building Code and Sewer Use Regulations. Undersizing is not a way to reduce cleaning cost; it increases both frequency and exposure.

We pump it and keep the manifests

Empire cleans grease traps across NYC with DEP-compliant disposal and the disposal manifests to prove it, on a recurring schedule set to your kitchen rather than a default interval.

Grease trap cleaning

Sourced from the NYC Department of Environmental Protection Disposing of Grease as a Business page and NYC Rules § 19-11. Verified 2026-09-02. The 25 percent rule is an industry operating convention, not a DEP requirement. Penalties change; check DEP before relying on any figure, including this one.