Grease Trap Cleaning Cost Per Gallon: A Comparison Method
Cost per gallon is arithmetic from a stated quote and capacity—not a universal service rate.
Define the denominator before calculating
Divide a written service quote by the unit's stated liquid capacity only when comparing similar equipment and the same service scope. Do not substitute grease-retention capacity or assume the full capacity equals the removed volume.
Scoped public-contract examples
The dated Washington Baker Commodities contract publishes provider-, county-, and volume-band prices. It is a contract example, not a national rate.
The dated Washington Clean Harbors contract publishes different provider and volume-band prices. The difference shows why scope and contract terms must travel with the number.
Local schedules can differ
Seattle guidance uses a 25 percent condition trigger.
Austin publishes a local maximum service interval of 90 days and an earlier fill trigger. These examples do not create a national rule.
Use a blank comparison table
| Proposal | Stated liquid capacity | Written visit total | Calculated quote ÷ capacity | Included scope |
|---|---|---|---|---|
| Provider A | Enter value | Enter value | Calculate | Record inclusions |
| Provider B | Enter value | Enter value | Calculate | Record inclusions |
Illustrative Per-Gallon Calculations
The capacity and service-price inputs below are examples chosen to demonstrate the arithmetic. They are not verified national rates. Replace them with the capacity on your equipment and written local quotes before budgeting.
| Example unit | Example stated liquid capacity | Example service price | Calculated price ÷ capacity |
|---|---|---|---|
| Small indoor unit | 35–100 gal | $115–$250 | $1.15–$7.14/gal |
| Mid-size unit | 100–500 gal | $200–$450 | $0.40–$4.50/gal |
| Large outdoor unit | 500–2,000 gal | $350–$750 | $0.18–$1.50/gal |
| Extra-large unit | 2,000–5,000 gal | $600–$1,500 | $0.12–$0.75/gal |
Under these example inputs, some larger capacities produce a lower calculated price per gallon because a visit can include costs that do not rise in direct proportion to tank capacity. The ranges still overlap, so larger does not automatically mean cheaper. Ask providers to explain what is included.
What Public Contracts Show
Two 2024 Washington State contracts demonstrate why one national range would be misleading:
- The Baker Commodities contract includes all-inclusive pumping and disposal rates around $0.70 per gallon up to 1,000 gallons and approximately $0.50–$0.55 per gallon for some 1,001–5,000-gallon county bands.
- The Clean Harbors contract lists approximately $3.54–$5.09 per gallon for 101–1,000 gallons, $1.31–$1.69 for 1,001–4,000 gallons, and $0.78–$1.06 for 4,001–25,000 gallons.
These are dated public-contract examples, not restaurant quotes or national averages. They show how provider, county, volume band, and contract scope can change the result.
Turn a Service Quote Into an Annual Budget
Multiply the written per-visit price by the required number of visits. These are conditional arithmetic examples, not market-rate claims:
- If biweekly service is quoted at $150, 26 visits × $150 = approximately $3,900 per year.
- If quarterly service is quoted at $400, 4 visits × $400 = approximately $1,600 per year.
- If quarterly service is quoted at $800, 4 visits × $800 = approximately $3,200 per year.
Use the locally required or measured service frequency. Do not assume a national schedule based only on equipment size.
Frequently asked questions
How do I calculate a per-gallon comparison?
Divide a written service quote by stated liquid capacity, and compare only similar equipment and the same service scope.
Is stated capacity the same as removed volume?
No. Do not present capacity as the amount pumped unless a service record documents the removed volume.
Is there one national rate per gallon?
No defensible national rate was established. The page uses scoped public-contract examples and user calculations instead.
Who sets the grease-trap rules for my property?
The authority serving the property sets the binding equipment, service, record, and enforcement requirements. Ask that authority for the current rule and keep the response with your service records.
Author: Grease Trap Locator Editorial Team
The Grease Trap Locator editorial team covers FOG compliance, grease trap maintenance, and commercial kitchen regulations across the US and Canada. Our guides are written for restaurant owners, facility managers, and food service operators who need practical, accurate information without the fluff.
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