BUI: What You Need to Know about U.S. Laws

March 24, 2026

Boating Under the Influence, or BUI (operating a vessel while intoxicated) is a serious violation of both federal and state law. The U.S. Coast Guard (USCG) maintains a zero-tolerance stance toward impaired boating because alcohol is a factor in many recreational boating deaths.

Key Takeaways

Boating Under the Influence (BUI) of alcohol or drugs is illegal across the United States.
Laws can vary according to state, but general regulations still apply, to boats of all types and sizes and on most U.S. waterways.
Impairment due to drug or alcohol consumption is made worse by the effects of boater fatigue, and it is up to the officer present to determine whether the boat operator is unfit to operate their vessel.

Dangers of BUI

Boating deaths are down in the United States, but in 2024, 20% of those deaths were linked with alcohol or drugs.

When you mix consumption with boating, it creates a dangerous combination of physical and mental impairments. In addition, the sun, wind, noise, vibration, and motion you are exposed to on a boat can induce boater fatigue, which makes the impact even worse.

Here are the 5 primary consequences of BUI:

1. Clouded Judgment

Alcohol and drugs make it much harder to think clearly and quickly, which means boaters make mistakes and fail to recognize dangers until it’s too late.

2. Physical Slowness

Coordination and balance quickly deteriorate when a person is under the influence of alcohol or drugs. This makes the likelihood of falling overboard much higher, and can also lead to falls and injuries while on board, helping someone reboard, or while using equipment.

3. Vision Problems

WHen under the influence, it becomes difficult to focus properly, and can be very hard to tell the difference between red and green navigation lights and to identify buoys and markers, which are key to safe navigation.

4. Higher Risk of Drowning

Alcohol messes with the inner ear. If a person falls overboard, they can become so disoriented that they cannot tell which way is up, making it impossible to swim to the surface.

5. Higher Risk of Hypothermia

Alcohol makes you feel warm even when your body is losing heat. A person in the water may not realize they are freezing until it becomes a life-threatening emergency.

BUI Laws in the United States

Keeping the waterways safe for all users is one of the responsibilities of every boat operator. BUI laws apply to all types and sizes of boats.

If you see a drunk boater, call 911 or contact the Coast Guard on your VHF Radio.

Federal Authority: 33 CFR Part 95

The primary federal regulation governing BUI is Title 33 of the Code of Federal Regulations (CFR), Part 95. It sets out the standards for deciding whether a person is impaired.

A boat operator is considered impaired if they have a Blood Alcohol Concentration (BAC) level of 0.08% or more.

Legal Limits

Even if a boater’s BAC is below the legal limit, they can still be charged if they behave as if they were impaired (remember, boater fatigue can play a role) as determined by an observing officer.

Jurisdiction: Where Federal BUI Law Applies

The USCG has the authority to enforce BUI laws on waters subject to the jurisdiction of the United States. This generally includes:

Internal waters (rivers, lakes, bays).
Seas extending 12 nautical miles from the baseline.
U.S.-flagged vessels outside territorial waters.

Federal vs. State Enforcement

While the USCG enforces federal law, states have their own BUI statutes. Learn more by reading our articles about BUI laws in New York, Florida and California.

BUI Penalties and Punishments in the U.S.

Violating BUI laws can result in both civil and criminal penalties under 46 U.S.C. § 2302.

If a boat operator is caught driving their recreational vessel while impaired, the USCG will typically force them to disembark, and their boat will be towed at the owner’s expense.
Fines for breaking the law (civil penalties) start at roughly $1000 and are usually higher.
If BUI leads to an accident or other criminal act, punishment can be a fine of up to $5000 and possibly also prison time.
An operator can also be fined if they refuse to be tested for drugs or alcohol.

Learn about boating laws with Drive A Boat USA

Safe boating involves knowing the law. Recreational boaters must carry appropriate safety equipment, follow established navigational rules, and operate their vessel in a responsible manner.

Find out what you need to know with a 100% online, NASBLA-approved boating safety course for U.S. boaters. All content meets U.S. Boating Education Standards and is designed to be easy and quick to learn.

At Drive A Boat USA, you can get your American state-specific boating license quickly and easily and go boating legally in California, New York or Florida today.