Pressure Washing Permit Requirements in Seattle, WA

1. EIN (Employer Identification Number)

   Required if you have employees or operate as an LLC/corporation. Free from the IRS.

   Official government source

   Free·Immediate (online)

   Free

   Immediate (online)

1. Washington State Business License

   Most Washington businesses must obtain a Business License from the Washington State Department of Revenue. This also serves as the sales tax registration.

   Official government source

   $50 (initial application processing fee)·~10 business days (online); up to 6 weeks by mail

   $50 (initial application processing fee)

   ~10 business days (online); up to 6 weeks by mail

2. Washington State Business & Occupation (B&O) Tax

   Pressure washing (specialized/exterior cleaning) is classified under Retailing B&O tax (0.471% of gross receipts) rather than Service & Other Activities, and businesses must also collect retail sales tax from customers on the service charge.

   Official government source

   0.471% Retailing B&O tax + retail sales tax on the service·Ongoing — file quarterly or annually

   0.471% Retailing B&O tax + retail sales tax on the service

   Ongoing — file quarterly or annually

3. General Liability Insurance

   Pressure washing businesses in Washington should carry general liability insurance ($1M minimum per occurrence) to cover property damage. Most commercial clients and property managers require proof of insurance before hiring. Vehicle insurance is also required if using a company vehicle.

   $500–$1,500/year·Same day (online quotes)

   $500–$1,500/year

   Same day (online quotes)

1. Seattle Business License Tax Certificate

   All businesses operating in Seattle, including pressure washing companies, must obtain a Business License Tax Certificate from Seattle License and Tax Administration before conducting commercial activity, and renew it annually through FileLocal. The certificate is required regardless of revenue. Seattle B&O tax is owed only above $2,000,000 in annual Seattle taxable gross revenue (threshold raised from $100,000 effective January 1, 2026, with a new $2,000,000 standard deduction), but you must still file and report gross revenue each year. Businesses with $4,000 or less of Seattle revenue and no place of business in the city are exempt from the certificate requirement as of 2026.

   Official government source

   2026 annual fee by Seattle taxable revenue: $73 (under $20,000), $147 ($20,000-$499,999), $667 ($500,000-$1,999,999), $1,604 ($2,000,000-$4,999,999), $3,210 ($5,000,000 or more), plus $10 per branch location. Businesses starting July 1 or later pay half the first-year fee.·Filed online through FileLocal the certificate is usually printable within 2-3 business days; by mail it takes one to six weeks. All certificates expire Dec. 31 and must be renewed annually.

   2026 annual fee by Seattle taxable revenue: $73 (under $20,000), $147 ($20,000-$499,999), $667 ($500,000-$1,999,999), $1,604 ($2,000,000-$4,999,999), $3,210 ($5,000,000 or more), plus $10 per branch location. Businesses starting July 1 or later pay half the first-year fee.

   Filed online through FileLocal the certificate is usually printable within 2-3 business days; by mail it takes one to six weeks. All certificates expire Dec. 31 and must be renewed annually.

2. Stormwater / Wastewater Discharge Compliance

   Pressure washing businesses in Seattle must comply with the state Water Pollution Control Act and Seattle's Stormwater Code, enforced by SDCI and Seattle Public Utilities. Wash water containing detergents, oils, or other pollutants may not be discharged to storm drains. Contain the wastewater and dispose of it to a sanitary sewer connection or an approved facility; confirm specific requirements with Seattle Public Utilities/SDCI and the Washington Department of Ecology.

   Official government source

   No permit or application fee - this is an ongoing compliance requirement. Costs are for containment and proper disposal equipment; violations of the Stormwater Code carry code-enforcement penalties.·Ongoing compliance, effective from the first job. There is no application or approval step.

   No permit or application fee - this is an ongoing compliance requirement. Costs are for containment and proper disposal equipment; violations of the Stormwater Code carry code-enforcement penalties.

   Ongoing compliance, effective from the first job. There is no application or approval step.

3. Trade Name (DBA) Registration

   If you operate under a trade name, register it with the Washington State Department of Revenue through the state Business License Application (RCW 19.80.010). King County does not file DBAs or fictitious business names.

   Official government source

   A trade name fee is charged per trade name, on top of the Business License Application processing fee: $50 if you are opening a new business, or $10 if you are adding a trade name to an existing licence.·Processed with the Business License Application: about 10 business days online, plus another 2-3 weeks if city or state endorsements need approval; up to 6 weeks by mail.

   A trade name fee is charged per trade name, on top of the Business License Application processing fee: $50 if you are opening a new business, or $10 if you are adding a trade name to an existing licence.

   Processed with the Business License Application: about 10 business days online, plus another 2-3 weeks if city or state endorsements need approval; up to 6 weeks by mail.

Official Sources

• City of Seattle — Business Licensing
• Washington Department of Environmental Quality
• Washington Secretary of State

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