New Hampshire DWI Laws & Penalties
Last reviewed:
NH says 'driving while intoxicated' (DWI). 'Aggravated DWI' at 0.16+ is a distinct enhanced charge.
Overview
- Legal BAC limit: 0.08% (commercial 0.04%, under-21 0.02%, enhanced at 0.16%).
- Lookback period: 10 years. 10-year lookback for second-offense treatment; some enhancements reference lifetime priors. Subsequent (4th within lifetime after prior felony) can be a felony.
- Primary statute: N.H. RSA 265-A:2 (offense); 265-A:18 (penalties)
0.16+ = Aggravated DWI (Class A misdemeanor) with mandatory jail (17 days min on first), longer suspension, and mandatory IID. Also aggravated: 30+ mph over, causing an accident, passenger under 16, or eluding.
Penalties by offense
| Offense | Classification | Jail | Fine | License suspension | Interlock |
|---|---|---|---|---|---|
| First offense | Class B misdemeanor (Class A / aggravated if 0.16+) | none (aggravated: 17 days, 12 suspendable → 5 mandatory) – aggravated: 1 year; mandatory min none base; aggravated 0.16+ = 17 days (5 unsuspendable) | $500–$2,000 ($500 + $120 penalty assessment (=$620) base; up to $2,000 aggravated) | 9 months – 2 years (18 months min aggravated); hardship: IID may be required; limited-driving 'reduction' possible after part of suspension | Not required |
| Second offense | Class A misdemeanor (within 10 years) | 17 days (or 30 days depending on recency; 3 days at a multiple-DWI intervention program) – 1 year; mandatory min 17 days (60 days if prior within 2 years, 30 in a treatment facility) | $750–$2,000 | 3-year revocation – 3 years; hardship: IID; possible reduction after 6 months | Required |
| Third offense | Class A misdemeanor | 180 days – 1 year; mandatory min 180 days | $750–$2,000 | indefinite (min 5 years before restoration petition) – indefinite; hardship: IID on restoration | Required |
First offense
- Classification: Class B misdemeanor (Class A / aggravated if 0.16+)
- Jail: none (aggravated: 17 days, 12 suspendable → 5 mandatory) – aggravated: 1 year; mandatory min none base; aggravated 0.16+ = 17 days (5 unsuspendable)
- Fine: $500–$2,000 ($500 + $120 penalty assessment (=$620) base; up to $2,000 aggravated)
- License suspension: 9 months – 2 years (18 months min aggravated); hardship: IID may be required; limited-driving 'reduction' possible after part of suspension
- Alternative disposition: Impaired Driver Care Management Program (IDCMP) required before reinstatement; no charge dismissal.
- Interlock: IID mandatory for aggravated (12–24 months after suspension) and repeat offenses.
Second offense
- Classification: Class A misdemeanor (within 10 years)
- Jail: 17 days (or 30 days depending on recency; 3 days at a multiple-DWI intervention program) – 1 year; mandatory min 17 days (60 days if prior within 2 years, 30 in a treatment facility)
- Fine: $750–$2,000
- License suspension: 3-year revocation – 3 years; hardship: IID; possible reduction after 6 months
Third offense
- Classification: Class A misdemeanor
- Jail: 180 days – 1 year; mandatory min 180 days
- Fine: $750–$2,000
- License suspension: indefinite (min 5 years before restoration petition) – indefinite; hardship: IID on restoration
- A subsequent DWI can be charged as a felony (Class B felony) under RSA 265-A:18 in some circumstances — verify at page QC.
Refusing a chemical test (implied consent)
Administrative License Suspension for refusal: 180 days (2 years if a prior DWI/refusal within 10 years), added on top of any conviction suspension; 30 days to request a hearing. Refusal admissible.
Statute: N.H. RSA 265-A:14, 265-A:30
Ignition interlock
IID mandatory for aggravated and repeat DWI (12 months–2 years after the revocation period); tied to the IDCMP reinstatement process.
Statute: N.H. RSA 265-A:36
Frequently asked questions
What is the penalty for a first DWI in New Hampshire?
A first DWI in New Hampshire is a Class B misdemeanor (Class A / aggravated if 0.16+). Jail: none (aggravated: 17 days, 12 suspendable → 5 mandatory) – aggravated: 1 year; mandatory min none base; aggravated 0.16+ = 17 days (5 unsuspendable). Fine: $500–$2,000 ($500 + $120 penalty assessment (=$620) base; up to $2,000 aggravated). License suspension: 9 months – 2 years (18 months min aggravated); hardship: IID may be required; limited-driving 'reduction' possible after part of suspension.
What is the legal BAC limit in New Hampshire?
0.08% for most drivers, 0.04% for commercial drivers, and 0.02% for drivers under 21.
How long does New Hampshire look back at prior DWI offenses?
10 years. 10-year lookback for second-offense treatment; some enhancements reference lifetime priors. Subsequent (4th within lifetime after prior felony) can be a felony.