New Hampshire · DWI · Checked October 2026
Ignition Interlock Rules in New Hampshire
Ignition Interlock Rules in New Hampshire: What Are the Rules?
When New Hampshire requires an ignition interlock after a DWI.
- First offense
- Required for aggravated DWI (12 months to 2 years after the revocation ends) and for any limited driving privilege; not required by statute for a basic first offense
- Repeat offenses
- Required for a second or later offense, 12 months to 2 years after the revocation ends
First Offense in New Hampshire
required for aggravated DWI (12 months to 2 years after the revocation ends) and for any limited driving privilege; not required by statute for a basic first offense
Repeat Offenses in New Hampshire
required for a second or later offense, 12 months to 2 years after the revocation ends
How the Program Works in New Hampshire
the interlock period starts only after driving privileges are fully restored; the device blocks starting at 0.020 or more; under 21: until age 21 or at least 12 months, whichever is longer; a fee reduction of up to 75% is available after a hearing if you can't afford it
More on DWI Law in New Hampshire
See the full overview of DWI laws in New Hampshire and read about how ignition interlock programs work.
This page summarizes New Hampshire law from official sources, checked October 2026. It isn't legal advice; a lawyer licensed in New Hampshire can advise on your case.
Frequently Asked Questions
Is an Ignition Interlock Required for a First DWI in New Hampshire?
required for aggravated DWI (12 months to 2 years after the revocation ends) and for any limited driving privilege; not required by statute for a basic first offense
Is an Interlock Required for Repeat Offenses?
required for a second or later offense, 12 months to 2 years after the revocation ends