How to Calculate and Bill Detention Pay

Detention pay is what a shipper or receiver, usually through the broker, pays you for holding your truck past the free time. Every hour at a dock is an hour you aren't driving and getting paid for miles. This guide covers how detention is worked out, how to handle rounding, overnight stops, and daily caps, and what to put on the invoice.

Where the terms come from

Detention is a contract term, not a set rate. Look for it on your rate confirmation or in your broker-carrier agreement. The terms that matter:

• Free time. How long you can be on site before detention starts, for example 2 hours.
• Hourly rate. What each hour past free time pays.
• When the clock starts. At check-in, or at your appointment time if you arrived early.
• Billing increment. Whether time is billed by the minute, in 15- or 30-minute steps, or by the whole hour.
• Cap. Some rate cons limit detention to a set amount per day or per stop.
• How to claim it. Who you have to notify, when, and what proof they want.

If the rate con says nothing about detention, ask for it in writing before you book, not after you've been waiting six hours.

The formula

Detention pay = (time on site − free time, rounded to the billing increment) × hourly rate, limited by any cap.

Worked example: a morning appointment

Your rate con says: 2 hours free, then $50 an hour, billed in 15-minute increments.

• Time in: 6:45 a.m. Time out: 12:20 p.m.
• Time on site: 5 hours 35 minutes
• Minus 2 hours free time: 3 hours 35 minutes
• Rounded down to 15 minutes: 3 hours 30 minutes, or 3.5 hours
• Detention: 3.5 × $50 = $175.00

If your rate con rounds up instead, 3 hours 35 minutes becomes 3 hours 45 minutes, and the bill is 3.75 × $50 = $187.50. That $12.50 difference is why the rounding rule matters. Bill it the way your rate con says. If it doesn't say, rounding down is the safe choice. You never bill for time you can't show, and the broker has less to push back on.

Worked example: an overnight stop

You check in at 9:30 p.m. on the 28th, and they finally release you at 4:15 a.m. on the 29th. Measure from date and time to date and time, not just clock time:

• Time on site: 6 hours 45 minutes
• Minus 2 hours free: 4 hours 45 minutes, which is 4.75 hours
• Already a whole number of 15-minute steps, so no rounding
• Detention: 4.75 × $50 = $237.50

Subtracting 9:30 from 4:15 without the dates gives a negative number, and it's an easy way to get overnight detention wrong. The detention pay calculator takes a date with each time for this reason.

Daily caps

If the rate con says detention is capped at, say, $400 a day, then 10 billable hours at $50 an hour ($500) pays $400. For a stop that runs past a full day, the calculator applies the cap to each 24 hours of billable time. Check how your rate con defines a "day". If it means something else, like a calendar day, work it out that way instead.

Waiting time and your hours of service

Detention also costs you driving time. Under the federal definition of on-duty time, time spent at a shipper's facility waiting to be dispatched, attending a truck being loaded or unloaded, or remaining in readiness to operate counts as on-duty time (49 CFR 395.2). The 14-hour limit counts 14 consecutive hours after you come on duty (49 CFR 395.3(a)(2)), so waiting at the dock uses up that window. The sleeper berth split in 49 CFR 395.1(g) is the main way around that, and it has its own conditions. A long wait can leave you legal to drive for only a few hours once you finally roll. Plan the rest of the trip with the hours of service calculator.

Getting it paid

• Record your times. Get in and out times on the BOL or gate log if you can, and keep your ELD record. Take a photo of the signed BOL.
• Notify the broker the way the rate con asks. If it says to call or send a message before free time runs out, do it while you're still at the dock. Write down who you talked to and any detention number they give you.
• Invoice promptly. Send the detention invoice with the rest of your paperwork, or on its own right after the load, whichever your broker wants.

What to put on a detention invoice

• Your company name and contact details
• Who you're billing: the broker or shipper
• Load or reference number, and any detention number
• Facility name and city
• Arrival and departure dates and times
• Free time, billable time, and how it was rounded
• Hourly rate and total due

The detention pay calculator fills all of that into a PDF invoice for you. If you're billing detention on the same invoice as the linehaul, add it as a line item in the freight invoice generator.