Working for a safe, affordable, vibrant, innovative, and interconnected city.
Learn More
Seattle.gov Home Page
Seattle.gov This Department
Link to Seattle Department of Planning and Development home page DEPARTMENT OF PLANNING & DEVELOPMENT

Property Line Changes

  • You need a land use permit to change your property line.

What Is It?

A property line change involves moving the property boundary between your property and the property next to yours. Most often, our customers want to move the property line of a single-family house.

You may want to move your property line to:

  • Include a building, such as your garage, that does not fully lie on your property
  • Correct a boundary disagreement between you and another property owner
  • Create lots that are each big enough to build upon

You cannot create a new lot by moving your property line.

What Permits Do You Need?

You need a land use plat permit to move your property line, or to create a new lot.

Research the Code

You need to show us that moving your property line will still maintain two lots which conform to our Seattle Municipal Code (SMC) and our building codes.

If your property is in a single-family zone (SF5000, SF7200, or SF9600), you need to follow the rules below. If your lot is in another land use zone, we may have different rules for you to follow; consult our land use code or ask our land use planners.

Minimum lot size. Your single-family lot must be at least 5,000, 7,200, or 9,600 square feet depending on which single-family zone your house is in.

Minimum yard size. Your single-family house can’t be too close to the property line in your front, side, and rear yards. Most often, we require your house to be 20 feet from the front property line, 5 feet from the side property line, and 25 feet from the back property line (or 10 percent of the lot depth if it is less than 25 feet).

Parking and access. Your single-family lot must meet our rules for parking and car access to your property. Usually, we require you to maintain the property’s parking spaces and access to them. At a minimum, we require one parking space per lot.

Regulations that govern environmentally critical areas. If your single-family lot is in an environmentally critical area, you must at the very least delineate the area on a drawing when you apply for a land use plat permit. We may have other requirements.

Utility service. Your single-family lot must meet our minimum levels of service for water, sewer, power, and fire access.

Fire separation between buildings. If you’re moving your property line, the line’s new location should be at least 5 feet from your single-family home, garage, and related buildings. In most cases, your buildings’ walls and eaves must be fire rated if they are less than 5 feet from your property line’s new location.

  • Seattle Residential Code R302

Should You Hire a Professional?

A licensed surveyor usually creates the documents for your land use plat permit application. You may create them if you can develop scaled drawings with lot lines, bearings, right-of-way information, building and lot line dimensions, and location of all utility services and trees.

What Do You Want To Do?


Still Need Help?


 Ask Us

  • Call us at (206) 684-8850
     
  • Visit the Applicant Services Center
    700 5th Avenue, 20th floor
    M, W, F: 8:00 a.m. - 4:00 p.m.
    T, Th: 10:30 a.m. - 4:00 p.m.
    (arrive before 2:00 p.m. for walk-in service)

 Online