1. Washington-specific invoice requirements
- Sales tax line: 6.50% state rate. Services billed to WA customers must include sales tax. State 6.5%; many services taxable. Combined commonly 8.5-10.5%.
- Late-fee cap: Washington statute Wash. Rev. Code §19.52.020 caps interest on unpaid invoices at 1.5% per month. Spell out the rate in writing on every invoice and in your contract — courts won't enforce undisclosed fees.
- Right-to-cancel notice: Customers in Washington get 72-hour cancellation rights on certain home-services contracts. Disclose this in your terms.
2. Freelance Developer line items + standard terms
Every freelance developer invoice in Washington should itemize work clearly. Standard freelance developers use Net 15 terms with a 25% deposit required upfront.
- Development — billed by hour (~$125 default).
- Project milestone — billed by flat.
- Third-party services — billed by passthrough.
3. Freelance Developer licensing in Washington
No license required. W-9 / 1099 reporting standard.
4. Send and follow up
Send the invoice the same day work completes. Use software that records open events and offers a one-click online payment so you don't need to chase a check by mail. Washington customers expect digital payment options today — accepting card and ACH typically reduces days-to-paid by 30–50%.
Washington metro guides
Metro-specific guides include the combined sales-tax rate and local pricing benchmarks.
- Invoicing as a freelance developer in Seattle
- Invoicing as a freelance developer in Spokane
- Invoicing as a freelance developer in Kennewick
- Invoicing as a freelance developer in Olympia
- Invoicing as a freelance developer in Bremerton
- Invoicing as a freelance developer in Yakima
- Invoicing as a freelance developer in Bellingham
- Invoicing as a freelance developer in Mount Vernon
- Invoicing as a freelance developer in Wenatchee
- Invoicing as a freelance developer in Longview
- Invoicing as a freelance developer in Walla Walla