Aftermarket Exhaust in Mississippi
Replacing the exhaust system is legal in Mississippi, but a muffler in good working order is required and cutouts or bypasses are prohibited.
Verified against primary sources · August 2026
What the law says
Replacing the exhaust system is legal in Mississippi, but a muffler in good working order is required and cutouts or bypasses are prohibited. Removing the catalytic converter is prohibited by federal law (Clean Air Act § 203) regardless of state rules. Mississippi repealed its inspection program in 2015.
Specific Limits
- Cutouts
- prohibited
- Muffler required
- Yes
- Catalytic converter
- removal prohibited by federal law
Exceptions & Exemptions
Exhaust system must include a muffler and cannot exceed noise levels that would constitute a public nuisance. Catalytic converters required on vehicles originally equipped with them. Cutouts, bypasses, or straight pipes that allow unmuffled exhaust are prohibited.
Frequently Asked Questions
Are aftermarket exhaust legal in Mississippi?
What are the exact aftermarket exhaust limits in Mississippi?
Are there exceptions for aftermarket exhaust in Mississippi?
Street-legal aftermarket exhaust picks
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