New Hampshire Trailer Brake Laws: Required Over 3,000 lb
New Hampshire RSA 266:30 requires adequate trailer brakes and exempts trailers under 3,000 lb only when the axle weight of the towed vehicle does not exceed 40% of the rated axle weights of the towing vehicle. House trailers over 1,500 lb are called out separately.
Quick answer: 3,000 lb gross weight
In New Hampshire, trailer brakes are currently listed at 3,000 lb (gross weight). New Hampshire measures gross weight, so weigh the trailer as you actually tow it.
| Requirement | State rule | Applies when | Source | Last checked |
|---|---|---|---|---|
| Trailer brakes | 3,000 lb | gross weight | Verified | 2026-07-13 |
| Breakaway switch | Needs verification | Trailer type and weight may matter | Verified | 2026-07-13 |
| Safety chains | Every trailer or semi-trailer, including farm and agricultural vehicles, must have a safety chain or cable in addition to the tow-bar, with ultimate strength at least equal to the gross weight of the trailer and load, connected to both towed and towing vehicle. One chain, not two, and no crossing is specified. | Conventional trailer couplings | N.H. Rev. Stat. Ann. 266:63 | 2026-07-13 |
| Speed / lane rule | A 45 mph maximum applies to any vehicle towing a house trailer. Other trailer types are not covered and follow the general limits. | Posted roads and vehicle combinations | N.H. Rev. Stat. Ann. 265:66(I) | 2026-07-13 |
| Double towing | Needs verification with New Hampshire statutes. | Multiple-trailer combinations | Verified | 2026-07-13 |
Official source links
New Hampshire RSA 266:30 requires adequate trailer brakes and exempts trailers under 3,000 lb only when the axle weight of the towed vehicle does not exceed 40% of the rated axle weights of the towing vehicle. House trailers over 1,500 lb are called out separately.
How the 3,000 lb threshold applies to three trailers
New Hampshire measures gross weight, so the weight of the trailer as loaded is what counts.
| Example trailer | Weight checked | Against 3,000 lb |
|---|---|---|
| Small utility trailer | 1,650 lb | Under the New Hampshire threshold by 1,350 lb |
| Loaded just under the line | 2,900 lb | Inside the New Hampshire limit, but one heavy load away from crossing it |
| Mid-size travel trailer | 4,800 lb | Over the New Hampshire threshold by 1,800 lb â brakes required |
New Hampshire trailer equipment rules
Safety chains
RequiredEvery trailer or semi-trailer, including farm and agricultural vehicles, must have a safety chain or cable in addition to the tow-bar, with ultimate strength at least equal to the gross weight of the trailer and load, connected to both towed and towing vehicle. One chain, not two, and no crossing is specified.
N.H. Rev. Stat. Ann. 266:63 âSpeed limit when towing
A 45 mph maximum applies to any vehicle towing a house trailer. Other trailer types are not covered and follow the general limits.
N.H. Rev. Stat. Ann. 265:66(I) âRead against the linked sources on . Statutes change and enforcement varies by trailer type â confirm before you tow.
Towing more than one trailer in New Hampshire
Needs verification with New Hampshire statutes.
Speed and lane rules when towing in New Hampshire
Needs verification; follow posted limits.
How New Hampshire compares with neighbouring states
None of the 3 states bordering New Hampshire set a stricter numeric brake threshold in this dataset, but bases and equipment rules still differ â check each state page before a trip.
| Bordering state | Brake threshold | Compared with New Hampshire |
|---|---|---|
| Maine | 3,000 lb gross weight | Same threshold |
| Massachusetts | 10,000 lb unladen weight | 7,000 lb more permissive |
| Vermont | 3,000 lb gross weight | Same threshold |
Planning a multi-state trip? The route brake law checker compares every state on a route at once.
Related towing tools
New Hampshire towing law FAQ
Are trailer brakes required in New Hampshire?
New Hampshire currently lists a trailer brake threshold at 3,000 lb gross weight. Always verify the official state source before towing.
What weight requires trailer brakes in New Hampshire?
The current data lists 3,000 lb gross weight as the brake threshold.
Is a breakaway switch required in New Hampshire?
The breakaway-switch rule for New Hampshire needs verification with official state sources.
Are safety chains required in New Hampshire?
Every trailer or semi-trailer, including farm and agricultural vehicles, must have a safety chain or cable in addition to the tow-bar, with ultimate strength at least equal to the gross weight of the trailer and load, connected to both towed and towing vehicle. One chain, not two, and no crossing is specified. (N.H. Rev. Stat. Ann. 266:63)
Can I tow two trailers in New Hampshire?
Needs verification with New Hampshire statutes.
Is there a towing speed limit in New Hampshire?
A 45 mph maximum applies to any vehicle towing a house trailer. Other trailer types are not covered and follow the general limits. (N.H. Rev. Stat. Ann. 265:66(I))
Does New Hampshire measure trailer weight as GVWR or actual weight?
New Hampshire uses gross weight, so weigh the trailer as you actually tow it rather than reading the data plate.
Where can I verify New Hampshire towing laws?
Start with the 2 official sources linked on this page, beginning with New Hampshire RSA 266:30 trailer brakes. Prefer state DOT, DMV, legislature, or public-safety pages over summaries from private websites. This page was last checked on 2026-07-13.