Wisconsin Trailer Brake Laws 2026: Required Over 3,000 lb
Wisconsin Statutes 347.35 requires brakes for trailers, semitrailers, or other towed vehicles of 3,000 lb or more gross weight manufactured after January 1, 1942, with exceptions that require trailer-type review.
Quick answer: 3,000 lb gross weight
In Wisconsin, trailer brakes are currently listed at 3,000 lb (gross weight). Wisconsin 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 | Wisconsin requires brakes on towed vehicles of 3,000 lb or more, but neither the statute nor the implementing rules requires an automatic breakaway device. Only air- or vacuum-braked combinations must have automatic emergency brake application. | Trailer type and weight may matter | Wis. Stat. 347.35(3); Wis. Admin. Code Trans 308.01, 305.51 | 2026-07-13 |
| Safety chains | In addition to the hitch and coupling, every towed vehicle must be coupled by safety chains, leveling bars or cables â two separate lengths on all trailers and mobile homes â connected so the drawbar cannot drop to the ground. Fifth-wheel semitrailers and pole or pipe dollies are exempt. | Conventional trailer couplings | Wis. Stat. 347.47(2), (3); capacity per Wis. Admin. Code Trans 308.12(4) | 2026-07-13 |
| Speed / lane rule | No towing-specific speed limit; follow posted limits. Fixed limits are 70 mph on freeways, 65 mph on expressways, 55 mph by default, 35 mph in semiurban districts and 25 mph in cities and villages. | Posted roads and vehicle combinations | Wis. Stat. 346.57(4) | 2026-07-13 |
| Double towing | Needs verification with Wisconsin statutes. | Multiple-trailer combinations | Verified | 2026-07-13 |
Official source links
Wisconsin Statutes 347.35 requires brakes for trailers, semitrailers, or other towed vehicles of 3,000 lb or more gross weight manufactured after January 1, 1942, with exceptions that require trailer-type review.
How the 3,000 lb threshold applies to three trailers
Wisconsin 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 Wisconsin threshold by 1,350 lb |
| Loaded just under the line | 2,900 lb | Inside the Wisconsin limit, but one heavy load away from crossing it |
| Mid-size travel trailer | 4,800 lb | Over the Wisconsin threshold by 1,800 lb â brakes required |
Wisconsin trailer equipment rules
Safety chains
RequiredIn addition to the hitch and coupling, every towed vehicle must be coupled by safety chains, leveling bars or cables â two separate lengths on all trailers and mobile homes â connected so the drawbar cannot drop to the ground. Fifth-wheel semitrailers and pole or pipe dollies are exempt.
Wis. Stat. 347.47(2), (3); capacity per Wis. Admin. Code Trans 308.12(4) âBreakaway system
Not required statewideWisconsin requires brakes on towed vehicles of 3,000 lb or more, but neither the statute nor the implementing rules requires an automatic breakaway device. Only air- or vacuum-braked combinations must have automatic emergency brake application.
Wis. Stat. 347.35(3); Wis. Admin. Code Trans 308.01, 305.51 âSpeed limit when towing
No towing-specific speed limit; follow posted limits. Fixed limits are 70 mph on freeways, 65 mph on expressways, 55 mph by default, 35 mph in semiurban districts and 25 mph in cities and villages.
Wis. Stat. 346.57(4) 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 Wisconsin
Needs verification with Wisconsin statutes.
Speed and lane rules when towing in Wisconsin
Needs verification; follow posted limits.
How Wisconsin compares with neighbouring states
None of the 4 states bordering Wisconsin 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 Wisconsin |
|---|---|---|
| Illinois | 3,000 lb gross weight | Same threshold |
| Iowa | 3,000 lb gross weight | Same threshold |
| Michigan | 3,000 lb gross weight | Same threshold |
| Minnesota | 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
Wisconsin towing law FAQ
Are trailer brakes required in Wisconsin?
Wisconsin 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 Wisconsin?
The current data lists 3,000 lb gross weight as the brake threshold.
Is a breakaway switch required in Wisconsin?
Wisconsin requires brakes on towed vehicles of 3,000 lb or more, but neither the statute nor the implementing rules requires an automatic breakaway device. Only air- or vacuum-braked combinations must have automatic emergency brake application. (Wis. Stat. 347.35(3); Wis. Admin. Code Trans 308.01, 305.51)
Are safety chains required in Wisconsin?
In addition to the hitch and coupling, every towed vehicle must be coupled by safety chains, leveling bars or cables â two separate lengths on all trailers and mobile homes â connected so the drawbar cannot drop to the ground. Fifth-wheel semitrailers and pole or pipe dollies are exempt. (Wis. Stat. 347.47(2), (3); capacity per Wis. Admin. Code Trans 308.12(4))
Can I tow two trailers in Wisconsin?
Needs verification with Wisconsin statutes.
Is there a towing speed limit in Wisconsin?
No towing-specific speed limit; follow posted limits. Fixed limits are 70 mph on freeways, 65 mph on expressways, 55 mph by default, 35 mph in semiurban districts and 25 mph in cities and villages. (Wis. Stat. 346.57(4))
Does Wisconsin measure trailer weight as GVWR or actual weight?
Wisconsin uses gross weight, so weigh the trailer as you actually tow it rather than reading the data plate.
Where can I verify Wisconsin towing laws?
Start with the 2 official sources linked on this page, beginning with Wisconsin Statutes 347.35 brakes. Prefer state DOT, DMV, legislature, or public-safety pages over summaries from private websites. This page was last checked on 2026-07-13.