Exhaust Noise in New Hampshire
New Hampshire sets no statewide decibel limit for passenger cars. A muffler in good working order is required, exhaust may not produce excessive or unusual noise, and cutouts or bypasses are prohibited.
Verified against primary sources · August 2026
What the law says
New Hampshire law is qualitative rather than numeric: A muffler in good working order is required, exhaust may not produce excessive or unusual noise, and cutouts or bypasses are prohibited. New Hampshire expressly bans straight pipes and carries escalating fines from $100 to $500 and above. Note that RSA 266:59-a's 92, 96, and 100 dB figures apply to motorcycles only — passenger cars have no decibel threshold.
Specific Limits
- Statewide decibel limit
- none
Frequently Asked Questions
Are exhaust noise legal in New Hampshire?
What are the exact exhaust noise limits in New Hampshire?
Street-legal exhaust noise picks
Gear that helps you mod without a ticket in New Hampshire.
Measure your exhaust at the test RPM before a fix-it ticket does.
Shop on AmazonA removable insert that brings a loud exhaust back under your state's limit.
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