Snohomish County Lot Splitting Rules (2026): What Homeowners Need to Know

Quick answer:

• Unincorporated Snohomish County: The County Council approved Ordinance 26-036 on October 14, 2026, creating an administrative lot-split process for residential parcels. Confirm its effective date with the county before applying.
• Cities (Edmonds, Lynnwood, Everett and others): State law (RCW 58.17.145) requires cities to allow administrative lot splits by July 27, 2027, unless their comprehensive plan update is due in 2027.
• The basics: One lot can become two, with no public hearing required before a decision on a qualifying split. A lot split does not by itself guarantee a buildable home site.

If you own a larger lot in Snohomish County, you may soon have a simpler way to divide it into two. On October 14, 2026, the Snohomish County Council approved Ordinance 26-036, creating an administrative lot-split process for residential parcels in unincorporated areas. The ordinance's final signature and effective date should be confirmed before applying the new process to a specific property. Cities across Washington generally have until July 27, 2027, to adopt their own procedures under state law, with a different timeline for cities whose comprehensive plan updates are due in 2027.

Here is what changed, who it applies to, and what to check before you count on it.

Please note: Rules, effective dates and eligibility vary by jurisdiction and by parcel. Before making any plans, check with Snohomish County Planning and Development Services (for unincorporated areas) or your city's planning department.

What is a lot split?

A lot split creates two separate lots that may be sold or transferred independently. Any future construction must still satisfy applicable zoning, building, utility and other permitting requirements. In other words, an approved lot split does not by itself guarantee a buildable home site.

Until now, splitting a lot usually meant a short plat: more steps, more review, and often a long wait. The new process is administrative. Planning staff review the application against clear standards, with no required public hearing before the decision.

Unincorporated Snohomish County: the approved county ordinance

The county's ordinance (Ordinance 26-036) applies only outside city limits, in unincorporated Snohomish County. The county's legislative record (File #2026-1908) shows the Council approved it as amended, 5-0, on October 14, 2026, but does not list an effective date. Confirm the effective date with the county before relying on it. As approved by the Council:

• Residential lot splits are reviewed administratively by the county's Planning and Development Services department.
• No public hearing is required before a decision on a qualifying split.
• Each split creates only one new lot, and both lots must be usable.
• Infrastructure requirements are limited to public right-of-way work, such as sidewalks and roads, as the code requires.
• Building on either lot still requires its own permits.

The county was not required to do this. It chose to use the state's 2025 lot-splitting law as a starting point.

Example: Esperance. Esperance is an unincorporated pocket of Snohomish County surrounded by Edmonds, so county rules, not Edmonds rules, apply there. Much of it is zoned R-8,400. That zoning is a starting point for evaluating lot size, not a guarantee that both resulting lots will qualify: the parcel's dimensions, density rules, access, setbacks and other development standards all still matter. Before planning a split there, confirm the ordinance's effective date and your parcel's eligibility with Snohomish County Planning and Development Services.

Cities: a statewide deadline of July 27, 2027

If your home is inside a city (Edmonds, Lynnwood, Everett, Mountlake Terrace, Bothell, Mill Creek, Marysville and others), the county ordinance does not apply. Instead, the state's 2025 lot-splitting law (HB 1096, codified at RCW 58.17.145) requires cities to add an administrative lot-split process to their own codes.

The lot-split requirement applies to cities without a population cutoff. Under RCW 58.17.145(14), cities whose next comprehensive plan update is due in 2027 must include it in that update. All other cities must implement it "within two years of July 27, 2025," which is July 27, 2027.

Some cities will move sooner. Everett, for example, is already drafting an update to its land division code. Until your city adopts its rules, splitting a lot there still goes through the city's existing process. Your city's planning department can tell you where it stands.

Which lots qualify (and which don't)

Under the state law, a lot split generally requires that:

• The lot is in a residential zone.
• Both resulting lots meet the zone's minimum lot size.
• Only one new lot is created, and that new lot can't be split again later.
• Sewer and water providers confirm service is available.
• Access and utility easements are in place before the survey is recorded.

Certain properties are excluded under state law, including areas that are not buildable under local development regulations (such as critical areas, shorelines, setbacks and lot coverage limits) and designated sole-source aquifer areas on islands in Puget Sound. Local rules and parcel-specific conditions still determine eligibility, and your city or county planning department makes the final call.

What this means for you

• Homeowners with larger lots: A second lot could mean a new home for family, a future sale, or added value. It's worth knowing whether your lot qualifies before you make long-term plans.
• Sellers: If your lot could be split, buyers and builders may value it differently. Knowing that before you list helps you price with confidence.
• Heirs and estate sellers: When settling an estate, split potential can change the options, from selling as is to dividing the property.
• Buyers: Lot-split potential can be part of a property's long-term value, but split potential is not the same as an approved, buildable second lot. Verify it with the city or county rather than assuming it.

Three questions to ask first

1. Is my property in a city or in unincorporated Snohomish County?
2. If it's in a city, has that city adopted its lot-split rules yet?
3. Does my lot meet the zone's minimum lot size, utility and access requirements?

Frequently asked questions

Can I split my lot in unincorporated Snohomish County?

Possibly. The County Council approved Ordinance 26-036 on October 14, 2026, creating an administrative lot-split process for residential parcels outside city limits. Confirm the effective date and your parcel's eligibility with Snohomish County Planning and Development Services.

Can I split my lot in Edmonds, Lynnwood or Everett?

The county ordinance does not apply inside city limits. State law requires cities to adopt an administrative lot-split process by July 27, 2027, unless their comprehensive plan update is due in 2027. Until your city adopts its rules, check with your city's planning department about its current process.

When do Washington cities have to allow lot splits?

Under RCW 58.17.145(14), most cities must implement the requirements within two years of July 27, 2025, which is July 27, 2027. Cities whose next comprehensive plan update is due in 2027 must include them in that update.

How many lots can I create?

One. A lot split turns one lot into two, and a lot created through a split cannot be split again.

Is a public hearing required?

Not for a qualifying split. State law calls for an administrative decision with no public hearing before the decision.

Does a lot split guarantee I can build a house?

No. Any future construction must still meet zoning, building, utility and other permitting requirements.

If you're wondering what this could mean for your property, I'm happy to talk it through and help you find the right answers from the city or county. Reach out anytime.

Disclaimer: This post is for general information only and is not legal, land use or tax advice. Lot-split rules, effective dates and requirements vary by jurisdiction and can change. Always confirm the details for your specific property directly with Snohomish County Planning and Development Services or your local city planning department, and consult a land use attorney, surveyor or other qualified professional before making decisions.

Erin Corwin is a real estate broker with The Corwin Group at Spire One Realty in Edmonds. Reach her at 206-650-7390 or [email protected].

Sources

• RCW 58.17.145: Residential lot splitting, administrative approval process
• Snohomish County Council, File #2026-1908 (Ordinance 26-036)
• Washington State Department of Commerce: Planning for Middle Housing, Residential Lot Splitting
• Department of Commerce: Residential Lot Splitting fact sheet
• The Everett Herald: SnoCo Council passes ordinance to make lot-splitting easier (Oct. 14, 2026)
• HB 1096 as passed by the Washington Legislature
• MRSC: 2025 subdivision legislation
• City of Everett staff memo on land divisions (July 7, 2026)
• My Edmonds News: Esperance zoning (Dec. 2025)