Yes you need a Seattle Business License.
The Seattle Business License Tax (a/k/a B & O Tax) is based upon Gross Receipts. It doesn't kick in until you have Gross Receipts of $100,000. As an example, the tax on $100,000. of Gross Receipts is $215.
All of the required filings may be done online at:
Once you are registered, you must file the Seattle Business Tax Returns even if you have -0- revenue and -0- tax due.
Also, you didn't ask about this so I presume that you know that you must also register with the State of Washington which also has a B & O Tax that must be paid if you have sufficient Revenue. If you need to reference those specific online filing requirements, you may do so at:
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