Real Estate Excise Taxes

Properties with Current Use Exemptions:

If you are submitting an excise affidavit to the Island County Treasurer's Office for processing and the property(ies) being transacted are in a current use program, you must first contact the Island County Assessor regarding the sale of the subject property(ies). The assessor's signature on the excise affidavit is required in order for us to process the transaction for you. This must be done in advance. 

Visit the Assessor's website for additional information about current use programs.

Affidavit Processing Hours are 9 a.m. to 3 p.m. weekdays.

Graduated REET rates

Real estate excise tax (REET) rates changed to a tiered/graduated rate system effective Jan. 1, 2020 under ESB 5998. In conjunction with this change, new state Department of Revenue affidavit forms are required for submission to the Treasurer's Office. Our website links to those new forms have been updated (see below). If you are completing these forms for your individual transaction, please be sure to use the correct one.

The Washington Department of Revenue's website features an excise tax calculator and information about property classifications for excise transactions to assist you in completing your affidavit.

Please note that it can take 10-20 minutes per document to process an excise transaction. Our office currently operates on a first-come, first-served basis. Check with a staff member regarding wait times.

For Title Companies, Lawyers, etc ...

Island County now accepts online transactions through Simplifile and CSCGlobal, which allow electronic processing of the excise tax affidavit by the Treasurer's Office and electronic recording by the Island County Auditor's Office. Contact us if your business has any questions about the eREET process or how to sign-up. Excise transactions may also be processed in person or by mail through the Treasurer's Office. Individuals wishing to process eREET transactions do not have access to this service at this time because of vendor guidelines.

Graduated REET Structure

Anytime real property or a mobile home changes hands, an affidavit completed through the Treasurer's Office is required. A Real Estate Excise Tax affidavit, along with a conveyance document (deed), must be presented to the Treasurer's Office for processing and collection of tax or fees due within 30 days of the sale/dated document. This is done prior to presenting that conveyance document to the Auditor's Office for recording. Visit the Washington State Department of Revenue's graduated REET structure for excise tax (plus a $5 transaction processing fee).

Each Real Estate Excise Tax transaction processed by the Island County Treasurer's Office is sent to and reviewed by the Washington Department of Revenue. The Department of Revenue will contact you directly if any questions or discrepancies are found by their office.

Effective immediately, and In keeping with the Washington State Department of Revenue (DOR) policy, the Island County Treasurer's Office no longer accepts excise affidavits submitted on 8.5 x 11 paper. The following documents must be printed on 8.5 x 14 paper:

  • Real Estate Excise Tax Affidavits,
  • Real Estate Excise Tax Supplement Statements

Affidavits that do not meet this standard will be rejected and returned to the submitter.


A transfer may be exempt from paying the real estate excise tax, but the proper Washington Administrative Code (WAC) must be cited on the affidavit.  A minimum fee of $10 will be charged for each affidavit presented to the Treasurer's office.

Access the Washington State Statutes and select the WAC code that most closely identifies with your situation and then click on the individual links. Read the requirements and documentation required BEFORE submitting your affidavit(s).

You may be required to fill out the supplement affidavit to obtain the exemption.

Sold/Bought a Mobile/Manufactured Home?

Sending your signed title to the state Department of Licensing will not change the ownership of the home. Every manufactered/mobile home sale must have the accompanying "Mobile Home Real Estate Tax Affidavit" completed along with the signed title, and brought to the Island County Treasurer's Office to pay the excise tax. All property taxes must be paid in full before the transfer can occur.

For more information about Real Estate Excise Tax Processing , call the Island County Treasuer's Office at 360-678-7841 or email