Boundary Line Adjustments

The Basics

A boundary line adjustment (BLA) is the process for adjusting property lines between legally created lots. This process cannot create a lot or reduce the size of a lot so that it contains insufficient area and dimension to meet minimum zoning or Snohomish County Health Department requirements, except as may be provided in code. Specific approval criteria and regulations are laid out in Chapter 30.41E of the Snohomish County Code. Depending upon site circumstances, a boundary line adjustment application may be routed for review by Transportation and the Snohomish County Health Department, in addition to Land Use. In cases where access is affected, staking proposed access points and property lines along the road frontage may be required.

At the time of application, prospective applicants will need to provide relevant documentation for review, including: an application, affidavit, certified legal descriptions and maps, and other supporting documentation. If the boundary line adjustment application involves more than two lots, a Record of Survey showing the new lot configuration must also be submitted. One copy of lot status documentation, ownership data, lot closures, and other relevant information, if applicable, should only be provided as a supplement to the original submittal package.

All owners with interest in the lots must provide original, notarized signatures to the affidavit. Spouses must both sign the document unless sole interest in property is by only one spouse. If someone is signing the affidavit on behalf of a company or corporation, a notary certification for the representative acknowledgement must be included. Additional sheets of signatures may be attached as necessary. All documents to be recorded must meet the Auditor’s Office recording requirements.

black and white image of a bondary line adjustement example

If the application is determined to be incomplete or more information is needed, PDS will notify the applicant in writing within 30 days of submittal. A decision will be made to approve, approve with conditions, or deny the application within 45 days following submittal of a complete application or revision. When review is complete, a written decision will be issued. This decision may be appealed by the administrative appeal process established by Chapter 30.70 SCC. If you wish to propose a boundary line adjustment, you are encouraged to contact the Customer Permitting Center about legal lot, access, and other boundary line adjustment requirements.

Fees. The most up to date fees can be found online at ch. 30.86 Fees | Snohomish County Code.

Submittal and resubmittal. Submit applications and corrections for Boundary Line Adjustments on See our online permitting page for more information. 

Forms and checklist 

Once Approved

Appeal. All boundary line adjustments are subject to the Snohomish County appeal procedures, which means that a 14-day appeal period is required once granted approval. Any aggrieved party-of-record may make a written appeal during this period. Should an appeal be made on the boundary line adjustment, the Snohomish County Hearing Examiner will consider the merits of the appeal. In such an instance, the boundary line adjustment approval would be placed on hold until a decision on the appeal is rendered by the Hearing Examiner. While applicants may choose to record their boundary line adjustment during this period, there is risk that a valid appeal could render the decision null and void if the County’s approval is reversed. 

Approved documents.  Approved BLA documents will be uploaded to your account and you will email notification. Print out the documents and record them with the Auditor's Office.  See Bulletin #99 for recording information (mailing vs. in person recording).

Payment of taxes and assessments. All current and delinquent taxes and assessments must be paid to the Snohomish County Treasurer (1st floor of the Robert J. Drewel Building) prior to the recordation of a boundary line adjustment. Current taxes and assessments mean any payments due during the calendar beginning on January 1st and ending on December 31st. These taxes and assessments must be paid on all properties associated with the boundary line adjustment. For boundary line adjustments that involve more than one party, each individual party will need to make payment. Upon receipt of all payments due, the Snohomish County Treasurer will issue an official verification that all taxes and assessments have been collected. This official verification is required by the Snohomish County Auditor in order to allow a boundary line adjustment to record. See RCW 84.56.345 for further information on payment of taxes and assessments.

Recordation. The boundary line adjustment only becomes effective upon recordation of the following items:

  • Affidavit of Boundary Line Adjustment;
  • Attachment of certified legal descriptions;
  • Attachment of boundary line adjustment map(s);
  • Record of Survey, if applicable; and
  • Conveyance documents, if applicable, that deed land to an adjoining property owner as part of the boundary line adjustment.

These documents should be brought to the Snohomish County Auditor (1st floor of the Robert J. Drewel Building) to be recorded upon the properties. Fees will be charged by the Snohomish County Auditor for each page to be recorded.

Return original documents. Once a boundary line adjustment has been recorded, the applicant must notify PDS of the recording numbers from the Auditor's Office via email or by uploading the recorded documents to their account.  This will complete the entire boundary line adjustment process.

Corrections to Boundary Line Adjustments. Typographical errors in recorded legal descriptions or minor discrepancies on BLA Affidavits may be corrected by filing an Affidavit of Correction of Boundary Line Adjustment with PDS. BLAs recorded with a Record of Survey will require a corrected Record of Survey that meets Washington State WAC standards. See link to instructions below which included items required on a corrected Record of Survey. If approved, the applicant shall record the Affidavit or corrected Record of Survey with the county Auditor within 45 days. Immediately after recording, copies of the recorded Affidavit or Record of Survey shall be provided to the department by the applicant. Corrections are limited to scrivener’s errors and typos. All other changes to boundary lines require submittal of a new BLA Application.

Expiration. The boundary line adjustment is valid for one year from the date of approval. It is incumbent upon the applicant to record the boundary line adjustment and all associated documents (e.g., conveyance documents and boundary line adjustment maps) before the one-year approval period lapses. The applicant may request an approval extension for an additional year if there is good cause for the County to do so. If neither of the above actions are taken, the boundary line adjustment approval will expire in full.