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New Hampshire Exhaust & Muffler Laws (2026)

Info: Your vehicle needs a muffler in good working order.

InfoVerified Jun 19, 2026

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Your vehicle needs a muffler in good working order. Cutouts, bypasses (which route exhaust around the muffler), and straight-pipe exhaust are prohibited. New Hampshire sets no decibel limit for cars — the decibel limit in 266:59-a applies only to motorcycles (N.H. RSA § 266:59).

Official source: gencourt.state.nh.us →

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