Snohomish County, WA Noise Ordinances: Quiet Hours (2026)
Quiet hours in Snohomish County, WA, also called the noise ordinance, nighttime noise rules, or residential quiet time, define the hours during which excessive noise is prohibited.
Key Facts
- Night hours, weekdays
- 10 p.m. to 7 a.m.
- Night hours, weekends
- 10 p.m. to 9 a.m.
- Nighttime reduction
- -10 dB(A) in rural/residential zones
- First infraction fine
- $100 residential / $250 commercial
- Repeat-offender misdemeanor
- Up to $1,000 per 24-hour violation
Summary
Every maximum permissible sound level in unincorporated Snohomish County drops by 10 dB(A) at night in rural and residential districts under SCC 10.01.030(3)(b). Night runs 10 p.m. to 7 a.m. on weekdays and 10 p.m. to 9 a.m. on weekends, per SCC 10.01.020(18).
(2) Maximum permissible sound levels. Measurement of sound levels from all sources except motor vehicles on public roads shall be made at or within the property boundary of the receiving property. ... (3) Modifications to maximum permissible sound levels. ... (b) At night, as defined in sub-section 10.01.020 (18), the maximum permissible sound levels are reduced by ten dB(A) where the receiving property lies within a rural or residential district of Snohomish county, except for sound sources exempted under sub-section 10.01.050 (3).
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through legislation passed August 12, 2026).
Full Breakdown
030 sets a table of maximum permissible sound levels, in dB(A), based on the zoning district of the noise source and the receiving property. A residential source affecting a residential receiver is capped at 55 dB(A) during the day, and rural-to-rural is capped at 49 dB(A). 020(18), the maximum permissible sound levels are cut by a flat 10 dB(A) wherever the receiving property sits in a rural or residential district, dropping that 55 dB(A) residential daytime cap to 45 dB(A) after dark. m. on Saturday, Sunday, and legal holidays, giving residents a later weekend cutoff.
A further 5 dB(A) reduction applies at night for periodic, pure-tone, or impulsive sounds under subsection (3)(c). 050(3), but only after advance written notice to the county noise administrator, posted signage at the plant, and mailed notice to nearby residents if the work runs more than two consecutive nights.
Violations & Fines
The Department of Planning and Development Services administrator enforces the quantitative nighttime standard under SCC 10.01.080(2), issuing either an administrative notice and order or a civil infraction under RCW chapter 7.80. Each infraction carries a $100 civil penalty for a non-commercial violator or $250 for a commercial one, doubling for a repeat violation of the same kind within three years. A person found to have committed three or more violations within three years faces a misdemeanor for any further violation within a year of the last adjudication, with a fine of up to $1,000 per 24-hour period the violation continues and possible mandatory installation of sound-measuring equipment at the violator's expense.
Frequently Asked Questions
When does Snohomish County's quiet-hours rule start each night?
How much quieter must things be at night in Snohomish County?
What's the fine for violating the nighttime noise limit?
Sources & Official References
Other rules in Snohomish County
How Snohomish County compares: Cities with the Strictest Noise Ordinances·Compare Snohomish County to another location·View the Washington noise ordinances overview
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