Most plumbing trip fees include the first hour on site. Bill only the hours beyond that, add parts, and the quote writes itself — with MAX keeping short calls from going negative.
An $89 trip fee, 2.5 hours at $110, and $40 in parts comes to $294 — and a 45-minute call stays at the base $89.
The example
Three calls, each with the trip fee, hours on site, hourly rate, and parts.
| A | B | C | D | E | F | |
|---|---|---|---|---|---|---|
| 1 | Job | Trip fee | Hours | Rate / hr | Parts | Total |
| 2 | Water heater leak | $89 | 2.5 | $110 | $40 | $294.00 |
| 3 | Clogged drain | $89 | 1 | $110 | $0 | $89.00 |
| 4 | Faucet replace | $89 | 1.5 | $110 | $65 | $209.00 |
The formula
MAX keeps the extra-hours term from going below zero:
How it works
The trip fee buys the first hour; everything after is billable:
B2is the trip fee, which includes the first hour of labor.MAX(0,C2-1)is the hours beyond the first — never negative, even on a 30-minute call.- Multiply the extra hours by
D2(your rate) and addE2for parts.
If your trip fee does not include labor, drop the -1 and bill every hour.
Try it: interactive demo
Enter the trip fee, hours on site, hourly rate, and parts.
Variations
No labor in the trip fee
If the trip fee is dispatch-only, bill all hours from the first minute.
Add a parts markup
Mark parts up before adding them to the ticket.
Pitfalls & errors
Without MAX(0,…), a 45-minute call computes negative labor and quietly discounts the trip fee.
Quote in quarter-hour steps — enter 1.25, 1.5, 1.75 — so the math matches how you actually bill.
Practice workbook
Frequently asked questions
Why subtract one hour?
Where does a parts markup go?
Stop fighting formulas. Learn them in a day.
This recipe is one of hundreds of real-world formulas we teach. Our Excel Formulas & Functions class covers lookups, logic, text, and dynamic arrays hands-on — live in Dallas–Fort Worth, Houston, Austin, Oklahoma City, Denver, or online.
See the Formulas & Functions Class