Hours of Service for Truck Drivers: The Limits and Their Exceptions

The federal hours-of-service rules for drivers of property-carrying commercial motor vehicles come down to a handful of numbers and a handful of exceptions. Most confusion comes from mixing the two up, or from forgetting that the 11-hour driving limit and the 14-hour window run on different clocks. This guide sets out the limits as they appear in 49 CFR 395.3, works through one schedule to show how they interact, and lists the exceptions found in 49 CFR 395.1.

The Limits at a Glance

Two details are easy to miss. First, the 14-hour window is a wall-clock limit: it keeps running while the driver waits at a dock, eats, or sits in traffic, because it counts consecutive hours from coming on duty. Second, the 30-minute interruption does not have to be off duty. The rule says it can be met by off-duty time, sleeper-berth time, on-duty-not-driving time, or a combination of those.

One Schedule, Worked Through

This is a hypothetical schedule, not a record of any real driver. A driver comes on duty at 06:00 after 10 consecutive hours off, and drives continuously until the break rule requires a stop.

• 06:00 to 14:00: 8 hours of driving. Driving time passes the 8-hour mark at 14:00, so a 30-minute interruption is needed before any more driving.
• 14:00 to 14:30: a 30-minute interruption, for example an on-duty-not-driving stop to fuel or inspect, or time off duty.
• 14:30 to 17:30: 3 more hours of driving, bringing the day's driving total to 11 hours.

At 17:30 the driver has reached the 11-hour limit, so driving must stop, even though the 14-hour window does not close until 20:00. The remaining two and a half hours of the window can be used for on-duty work that is not driving, but not for driving. So on a day with delays at the dock the window can run out before the driving hours do, and on a clean day it is the other way round.

Exceptions Written Into the Rule

49 CFR 395.1 sets out exceptions to the limits above. These are the ones most relevant to general freight, each paraphrased from the regulation text:

• Adverse driving conditions. Some conditions could not reasonably have been known before the duty day began. If a driver meets them and cannot safely finish the run within the normal limits, the driver may drive up to two additional hours. That time is for completing the run or reaching a place offering safety and security for the occupants, vehicle and cargo. Section 395.2 defines the term as snow, ice, sleet, fog, or other adverse weather, or unusual road or traffic conditions, not known or reasonably knowable to the driver or the carrier at dispatch. Conditions the driver could have anticipated do not qualify.
• Emergency conditions. In an emergency, a driver may complete a run without violating the rules if the run could reasonably have been completed absent the emergency.
• Short-haul, 150 air-mile radius (CDL drivers). A driver is exempt from the record-of-duty-status requirement of 395.8 if four things are true. The driver operates within 150 air miles (172.6 statute miles) of the normal work reporting location. The driver returns and is released within 14 consecutive hours. The driver has at least 10 consecutive hours off duty separating each 14 hours on duty. And the carrier keeps accurate time records for six months.
• Short-haul, 150 air-mile radius (non-CDL property carriers). A driver of a vehicle that does not require a CDL may be exempt from the 14-hour window and the record of duty status. The driver must operate within 150 air miles and return at the end of each duty tour. The driver must also not drive after the 14th hour on five days of any seven consecutive days, nor after the 16th hour on the other two. The carrier keeps time records for six months.
• Sleeper berth. A driver using a sleeper berth to obtain the required 10 hours off may split it. One option is two periods, neither shorter than two consecutive hours, one at least seven consecutive hours in the sleeper berth, totaling at least 10 hours. The rule also allows a combination of at least seven consecutive hours of sleeper-berth time and up to three hours riding in the passenger seat of the moving vehicle.
• Oilfield operations. For drivers of vehicles used exclusively in oilfield service, an 8-day period may end with an off-duty period of 24 or more successive hours.

Whether any of these applies depends on the details of the operation. Confirm the full wording of 395.1 before relying on one, especially for the short-haul exceptions, which carry conditions beyond the summary above.

Does the 14-hour window stop when I take a break?

No. Under 395.3(a)(2) the window is measured as 14 consecutive hours after coming on duty, so breaks, waiting and loading all use up the window. The one exception is a qualifying sleeper-berth split: under 395.1(g)(1)(iii), the 14-hour window does not include qualifying rest periods.

Do truck drivers still keep a paper logbook?

In most cases no. Under 49 CFR 395.8, carriers generally must require drivers to record duty status with an electronic logging device (ELD). Paper records are allowed in limited cases. They include drivers who need a record of duty status on no more than 8 days in any 30-day period, certain driveaway-towaway operations, and vehicles manufactured before model year 2000.

Passenger-carrying drivers follow different limits in 49 CFR 395.5. Personal conveyance is handled through FMCSA guidance rather than the rule text. Drivers who stay inside one state may be held to that State's limits instead. The seven-day record of duty status mentioned above is one of the things checked at the roadside; see Commercial Vehicle Roadside Inspections: What Each Level Covers.

Sources

Regulation text: eCFR, current as of 7 October 2026.

• 49 CFR § 395.3 — Maximum driving time for property-carrying vehicles
• 49 CFR § 395.1 — Scope of rules in this part
• 49 CFR § 395.2 — Definitions