Aftermarket Exhaust in Vermont
Replacing the exhaust system is legal in Vermont, but a muffler in good working order is required and cutouts or bypasses are prohibited. There is no statutory 'no louder than stock' rule — the standard is that the exhaust must not produce excessive or unusual noise.
Verified against primary sources · August 2026
What the law says
Replacing the exhaust system is legal in Vermont, but a muffler in good working order is required and cutouts or bypasses are prohibited. There is no statutory 'no louder than stock' rule — the standard is that the exhaust must not produce excessive or unusual noise. Removing the catalytic converter is prohibited by federal law (Clean Air Act § 203) regardless of state rules. Vermont enforces exhaust condition through its general good-mechanical-condition requirement plus annual safety and OBD inspection. S.66, which would have added express prohibitions on gutted mufflers, straight pipes, and cutouts, passed the Senate but died in House Transportation on May 29, 2026 — Vermont law is unchanged.
Specific Limits
- Cutouts
- prohibited
- Muffler required
- Yes
- Louder than stock
- not addressed; excessive noise standard applies
- Catalytic converter
- removal prohibited by federal law
Exceptions & Exemptions
Must have functioning muffler that prevents excessive noise. Catalytic converter required for vehicles originally equipped. No straight pipes or bypasses allowed. Sound level restrictions apply.
Frequently Asked Questions
Are aftermarket exhaust legal in Vermont?
What are the exact aftermarket exhaust limits in Vermont?
Are there exceptions for aftermarket exhaust in Vermont?
Street-legal aftermarket exhaust picks
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