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Maryland Exhaust & Muffler Laws (2026)

Info: Your vehicle needs a muffler in good working order, and muffler cutouts and bypasses (which route exhaust around the muffler) are prohibited, as are tailpipe extensions that amplify noise.

InfoVerified Jun 19, 2026

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Your vehicle needs a muffler in good working order, and muffler cutouts and bypasses (which route exhaust around the muffler) are prohibited, as are tailpipe extensions that amplify noise. Maryland sets no fixed decibel limit (Md. Transp. § 22-402).

Official source: mgaleg.maryland.gov →

General legal information, not legal advice — verify important decisions with a licensed attorney.

Exhaust & Muffler in states bordering Maryland

The same rule in each neighboring state LawLert has verified, from that state’s own official source.

DelawareInfo
Your vehicle needs a muffler in good order, and muffler cutouts (which route exhaust around the muffler) are prohibited — it's also unlawful to sell a gutted muffler, a cutout, or straight pipe. Delaware sets no fixed decibel limit (21 Del. C. § 4311).
Verified Jul 22, 2026 · Source: delcode.delaware.gov · Full Delaware rule →
District of ColumbiaInfo
You can't modify your exhaust in a way that pushes noise above the legal limits — D.C. sets decibel caps for vehicles in use in a table, for example 88 decibels measured at 50 feet (20 DCMR §§ 2811-2812).
Verified Jun 19, 2026 · Source: dcrules.elaws.us · Full District of Columbia rule →
PennsylvaniaInfo
Your vehicle needs a muffler. Cutouts, bypasses (which route exhaust around the muffler), and noise-amplifying changes are prohibited. Sound limits are set by Department regulation; the statute itself sets no fixed decibel number (75 Pa.C.S. § 4523).
Verified Jun 19, 2026 · Source: legis.state.pa.us · Full Pennsylvania rule →
VirginiaInfo
Your vehicle needs an exhaust system in good working order so it doesn't make excessive or unusual noise, and chambered pipes count as a violation. Virginia sets no fixed decibel limit (Va. Code § 46.2-1049).
Verified Jun 19, 2026 · Source: law.lis.virginia.gov · Full Virginia rule →
West VirginiaInfo
Your vehicle needs a muffler — factory (OEM) or equivalent — in good working order, and a cutout, bypass or similar device (which routes exhaust around the muffler) is prohibited. West Virginia sets no fixed decibel limit (W. Va. Code § 17C-15-34).
Verified Jun 19, 2026 · Source: code.wvlegislature.gov · Full West Virginia rule →

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