Hours of service rules are the FMCSA limits on how long a truck driver can drive and work before resting. For drivers of property-carrying trucks, the core rules are an 11-hour driving limit, a 14-hour on-duty window, a 30-minute break after 8 hours of driving, and 60 or 70-hour weekly limits.
The rules apply to the driver, not to you. But a dispatcher who books a load the driver cannot legally deliver on time has made a problem for everyone. Here is how the core rules work and how to plan loads around them.
Key takeaways
- Hours of service rules come from FMCSA and limit driving time, on-duty time and weekly hours.
- The 14-hour window keeps running during loading, waiting and breaks, so a long wait at the dock can end the driver’s day early.
- Always ask the driver how many hours they have left before you book a load.
- Never pressure a driver to drive past their hours. Plan the load so they do not have to.
- Rules have exceptions and can change. Check the current rules on the FMCSA website.
What are the hours of service rules for truck drivers?
The hours of service rules for property-carrying drivers set daily limits, a break rule and weekly limits. FMCSA publishes them in its regulations (49 CFR Part 395), and the table below is a plain-language summary of the core rules, not the full text.
| Rule | What it means | Why it matters to a dispatcher |
|---|---|---|
| 10 hours off duty | A driver needs 10 consecutive hours off duty before a new driving day starts | You cannot schedule the next pickup until the driver’s reset is done |
| 11-hour driving limit | After 10 hours off, a driver may drive up to 11 hours | Long runs may need to be split across two days |
| 14-hour window | A driver may not drive after the 14th hour from coming on duty, and breaks do not extend it | Waiting at shippers and receivers uses up this window |
| 30-minute break | A 30-minute break from driving is required after 8 hours of driving in total | Add the break to your transit time |
| 60/70-hour limit | A driver may not drive after 60 hours on duty in 7 days, or 70 hours in 8 days, depending on the carrier’s schedule | A driver near the weekly limit may have few hours left for your load |
| 34-hour restart | A driver can restart the 7 or 8-day period by taking 34 or more consecutive hours off duty | The restart affects when the driver is available again |
There are also exceptions and options, such as rules for short-haul drivers, adverse driving conditions and splitting rest time in the sleeper berth. These have their own conditions, so read the details on the FMCSA website before you rely on one.
How does the 14-hour window work?
The 14-hour window starts when the driver comes on duty after 10 hours off, and the driver may not drive after it ends. It keeps running whether the driver is driving, loading, waiting or taking a break.
This is the rule that catches new dispatchers. A driver may have plenty of the 11 driving hours left, but if they spent the morning waiting at a shipper, the 14-hour window may close before the driving hours run out. On-duty time that is not driving, such as loading, inspections and fueling, also counts toward the weekly limit.
That is one reason detention matters. Time stuck at a dock costs the carrier money and eats into the hours the driver needs to deliver.
How do dispatchers plan loads around hours of service?
Dispatchers plan around hours of service by checking the driver’s available hours first and then building a realistic trip plan. A few minutes of planning prevents late deliveries and pressure on the driver.
- Ask for the driver’s hours. How many driving hours, how much of the 14-hour window, and how many weekly hours are left.
- Check the appointment times. Look at pickup and delivery windows on the rate confirmation, and whether they are set appointments.
- Estimate the drive time. Use realistic speeds for the route, not the best case, and allow for traffic and weather.
- Add the stops. Include the 30-minute break, fuel stops, loading time and any 10-hour rest the trip needs.
- Watch the time zones. A delivery listed in local time may be an hour earlier or later than the driver’s clock.
- Leave a margin. If the plan only works when nothing goes wrong, the load is too tight. Ask the broker for a different appointment or pass on the load.
Our free HOS Trip Planner helps you estimate drive time, breaks and rest stops for a trip. For more on clocks and routes, read our guide to topography and time zones in truck dispatching.
A worked example
The times below are an example only, to show how the rules interact.
A driver finishes 10 hours off duty and comes on duty at 6am. The 14-hour window will end at 8pm.
- The shipper is slow, and the driver waits and loads until 9am. That is 3 hours on duty, not driving.
- The driver drives from 9am to 5pm. That is 8 hours of driving, so a 30-minute break is now required.
- After the break, the driver drives from 5:30pm until 8pm, when the 14-hour window closes.
The driver has driven 10.5 hours, still under the 11-hour limit, but must stop at 8pm because the 14-hour window has ended. If the delivery was planned for 10pm that night, it was never possible. Seeing this before you book is the job.
What happens if a driver runs out of hours?
If a driver runs out of hours, they must stop and take the required rest before driving again. A violation can lead to fines and being put out of service, and it can hurt the carrier’s safety record.
When a load is at risk, tell the broker early, give a realistic new time, and get any change in writing. FMCSA also has a rule against coercing drivers to break safety rules, including hours of service. As a dispatcher, your job is to plan, not to push.
Our guide to what a truck dispatcher does each day shows how trip planning fits into the rest of the workday.
This is general information, not legal advice. Rules change and have exceptions, so always check the current hours of service rules on the FMCSA website.
Frequently Asked Questions
Does the 30-minute break have to be off duty?
No. Under the current FMCSA rule, the break can be any 30 consecutive minutes when the driver is not driving, such as off duty, in the sleeper berth or on duty but not driving.
Do hours of service rules apply to dispatchers?
No. The rules limit the driver’s time behind the wheel. Dispatchers need to know them because the loads they book must fit inside the driver’s available hours.
Does waiting at a shipper count against the driver’s hours?
Yes, in most cases. Time waiting on duty at a shipper or receiver runs on the 14-hour window and counts toward the weekly limit.
How do drivers track their hours?
Most drivers who must keep records of duty status use an electronic logging device, or ELD. Ask the driver or carrier how they share their available hours with you.
Learn to plan loads the right way
Booking loads a driver can legally deliver is part of the daily work Dispatcher 101 teaches, with sections on Logistics, Finding Freight and Booking Your First Load. Students on both plans can ask Joe Piazza about a tricky trip through 1-on-1 mentorship, and the Gold plan adds templates, 12 months of load board access and a 14-day money-back guarantee.
