Grease trap cleaning guide

A grease trap (also called a grease interceptor) catches fats, oils and grease (often shortened to FOG) before they reach the public sewer. Cities regulate them because grease that gets past them clogs sewer lines and causes overflows^[1]. This guide covers what is usually required, what it costs, and how to pick a hauler.

How often is cleaning legally required?

There is no single national rule; your city or sewer utility sets it. Most use two triggers: a maximum number of days between pump-outs, and a fill level that forces an earlier pump-out. Examples from cities we cover:

City	Rule	Records
Austin, TX	At least once every three months, or sooner if grease and solids reach 50% of the wetted height^[2]	Manifests kept up to three years^[2]
Houston, TX	Only a transporter permitted by the Houston Health Department may clean the trap^[3]	Manifest copies kept on site at least five years^[3]
New Orleans, LA	Frequency depends on buildup, but at a minimum every 90 days^[4]	Food service establishments need a Grease Trap Interceptor Discharge Permit^[4]

The U.S. Environmental Protection Agency notes that how often a trap needs service depends on how much grease a kitchen produces, and that kitchens using best management practices (for example, collecting used fryer grease for pickup and recycling instead of pouring it down the drain) can often reduce how often their trap must be serviced^[1]. They do not replace your city's minimum schedule.

What does grease trap cleaning cost?

We have not run our own price survey. The ranges below are published by third-party industry guides, and actual quotes vary a lot by city, trap size and condition.

Trap size	Published range per cleaning	Who published it
Small under-sink trap, 20–50 gallons	$150–$300	FindGreaseTrapServices.com^[5]
Medium under-sink / small in-ground, 50–200 gallons	$250–$500	FindGreaseTrapServices.com^[5]
Large in-ground interceptor, 500–1,500 gallons	$500–$1,200	FindGreaseTrapServices.com^[5]
Very large interceptor, 1,500–2,500+ gallons	$1,000–$2,000+	FindGreaseTrapServices.com^[5]
Indoor 30–200 gallons on an ongoing schedule	$125–$180	Grease-Cycle, as compiled by The FOG Desk^[6]

Emergency or after-hours service often costs more; one published guide puts it at 1.5–2 times the standard rate^[6].

What moves the price

Trap size and type. Small indoor traps cost less per visit than big outdoor interceptors.
How long since the last pump-out. Hardened grease and heavy solids take longer to remove.
Access. Long hose runs, buried lids and tight alleys add time.
Frequency and contract. Regular scheduled service is usually cheaper per visit than one-off calls.
Disposal fees at the receiving facility, which vary by region.

Pumping vs. hydro-jetting

Pumping means a vacuum truck removes everything in the trap: floating grease, water and the solids on the bottom. This is the service your city's schedule is talking about, and it is what the manifest records.

Hydro-jetting means blasting the drain lines with high-pressure water to clear grease buildup inside the pipes between your kitchen and the trap (or the trap and the sewer). It is a line-cleaning service, not a substitute for pumping. Many haulers offer both; if your drains back up between pump-outs, jetting the lines may help. Ask whether the jetting debris is captured and removed rather than pushed down the line.

What to ask a hauler before you hire

Do you hold the permit my city requires? Ask for the permit number, then check it against the official list.
Will you pump the trap completely (grease, water and settled solids), or just skim the top?
Will I get a signed manifest for every visit? Who keeps copies and for how long?
Where does the waste go? It should go to a licensed disposal or recycling facility.
Is the price per visit, per gallon, or per hour? What triggers extra charges (long hose runs, heavy solids, after-hours, emergency calls)?
Do you measure the grease and solids layers and tell me if I should pump more or less often?
Do you also inspect baffles and report damage? Repairs are often separate.
What is the minimum contract length, and how do I cancel?

Related services

Kitchen hood and exhaust cleaning

Hood cleaning is a fire-safety service, separate from your grease trap. The fire code standard NFPA 96 sets how often the exhaust system must be inspected for grease buildup: monthly for solid-fuel cooking, quarterly for high-volume cooking (such as 24-hour, charbroiling or wok cooking), twice a year for moderate volume, and once a year for low volume^[7]. It is cleaned when the inspection finds buildup past the standard's limits. Your fire marshal or insurer may have its own requirements.

Used cooking oil pickup

Fryer oil should never go down the drain. In Houston, used frying grease must be picked up by a private disposal company^[3]. Renderers and recyclers often provide a storage container and collect on a schedule; some of the companies on our city pages offer both trap pumping and oil pickup.