DWI in New Hampshire: the law, the limits and the device
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New Hampshire calls it DWI — driving while intoxicated, and you will see DUI and drunk driving used for the same offense. What follows is what this state sets, taken from its own published rules rather than from a national summary.
What New Hampshire law actually requires
New Hampshire runs the program through the DMV and the courts together: a court or the Commissioner of Safety orders the device, and you may drive only vehicles fitted with a New Hampshire-approved one. The certificate of installation goes to the DMV yourself, not through the vendor. If you cannot afford it, RSA 265-A:36 allows a hearing for a credit of up to 75% of installation and service costs.
- First offense: Ordered by a New Hampshire court or by the Commissioner of Safety under RSA 265-A:36; you may only drive vehicles fitted with a NH-approved device
- Lockout threshold: Set by the preset level in the approved device: RSA 259:43-a defines it as blocking the engine unless the sample is below that level
- Program run by: NH Division of Motor Vehicles, or the court
Source: www.dmv.nh.gov, checked 2026-08-23
DUI vs DWI in New Hampshire
New Hampshire uses DWI, and the difference from plain DUI is worth getting right: both describe driving impaired, and locally the charge is written as DWI — driving while intoxicated
Whatever it is called, the licensing consequence is the same shape: a suspension, then the device as the condition of driving again. All six abbreviations, side by side →
Can you get a DWI on a bike or a horse in New Hampshire?
It turns on one word in the statute. Where the law says “vehicle”, no engine is required and the charge can reach a bicycle, a horse or a mobility scooter. Where it says “motor vehicle”, the analysis is different. This is decided by your state’s own wording, not by national custom, and it is the first thing to check before assuming a bike ride home is safe.
How often this happens in New Hampshire
Federal crash records show the scale the state is legislating against, and how it compares with the country.
Cases are heard where the stop happened, and volume shapes local practice. These NH counties record the most:
Source: NHTSA Fatality Analysis Reporting System, 2020–2022. Counts crashes where police recorded that a driver had been drinking, which is narrower than the federal 0.08 measure and therefore understates the real figure. New Hampshire runs above the national share.
What it costs to get driving again in New Hampshire
New Hampshire does not publish a price cap we could verify, so the quote is the number and your only leverage is a competitor nearby. The national reference points are installation and a monthly fee, with calibration visits every 30 to 60 days.
New Hampshire costs, providers and all 55 cities with centers →
The two clocks in New Hampshire
The court case and the licensing case run separately. The licensing side moves first, and in the strictest states the window to request a hearing is measured in days — it runs whether or not you have hired anyone.
DWI questions in New Hampshire
Is it called DUI or DWI in New Hampshire?
New Hampshire uses DWI — driving while intoxicated. You will also see DUI, drunk driving used for the same thing. The label follows the state, not the seriousness of what happened, so paperwork from elsewhere may say something different about identical conduct.
What is the legal limit in New Hampshire?
0.08% for drivers 21 and over, as in every state except Utah, which sits at 0.05%. Below the limit you can still be charged if an officer documents impairment. The reading that triggers the interlock here is a separate number: Set by the preset level in the approved device: RSA 259:43-a defines it as blocking the engine unless the sample is below that level
How long does the interlock stay on after a first offense in New Hampshire?
Ordered by a New Hampshire court or by the Commissioner of Safety under RSA 265-A:36; you may only drive vehicles fitted with a NH-approved device The program is run by NH Division of Motor Vehicles, or the court.
Can you get a DWI on a horse or a bicycle in New Hampshire?
The answer is in whether the statute says “vehicle” or “motor vehicle”. Where it says vehicle, no engine is needed and the charge can reach a bike or a horse; where it says motor vehicle, it cannot. This is one of the most searched questions in the whole subject and one of the most confidently answered wrongly — the wording of your own state decides it.
A second DWI here →A first DWI here →
When a charge becomes a felony → The test and the refusal → SR-22 and FR-44 →
Attorney advertising. InterlockDeviceNearMe is not a law firm, does not practice law, and does not give legal advice. Nothing here creates an attorney-client relationship. Requesting a consultation connects you with an independent attorney or a legal referral service, who decide separately whether to take your case. Case outcomes depend on facts we do not know, and no result is ever promised. Deadlines in DUI cases are short and vary by state — speak to a licensed attorney in your state before relying on anything you read here.