The first answer in the City of Mill Creek's annexation FAQ sounds like good news for the roughly 11,700 people living just south of the city line. Their property-tax levy would go down, and the City estimates the saving at about $250 a year on an $850,000 home. The next sentence of the same answer says those households would also start paying Mill Creek's 5% utility tax, estimated at $327 to $423 a year.
Put those two figures side by side and the City's own estimate for an $850,000 home works out to a slightly higher combined bill. For anyone buying in the proposed annexation area over the next year, that matters less than what it shows about the whole process. A home in Mill Creek South comes with a likely change of city during ownership. The tax effect is small and roughly even. The bigger unknowns are which rules, providers and timeline will apply, and the City is still deciding them.
The City's numbers, side by side
Here is the City's FAQ example for a home assessed at $850,000:
| Item | City estimate | Direction |
|---|---|---|
| Annual property-tax change | About $250 less | Saving |
| New 5% city utility tax | $327 to $423 per year | New cost |
| Combined, by the City's figures | About $77 to $173 more per year | Slightly higher |
The last row is simple subtraction from the City's own estimates. The FAQ adds that the utility tax would be lower for households without cable service. All of these figures are estimates. None of them is an adopted rate. The effect on any one household will depend on its assessed value and its utility bills.
A difference of about $100 a year won't decide whether someone buys a house. What the table does show is that this annexation is not a tax cut for the people being annexed. The City is open about the reason for annexing, and that reason explains the rest of the process.
Why the City wants it: revenue, not rates
The City asked SME Consulting for a financial analysis. It estimated that annexing Mill Creek South would bring the City about $2.7 million a year in net revenue starting in year one, growing to about $5.3 million a year by 2045. Most of that comes from the area itself. The October 13 council packet lists "Gains Hwy 527 commercial corridor" among the benefits and says the area's industrial zoning "provides economic development opportunity."
The Council's own guiding principles require that the first annexation produce "substantive net-positive financial returns to the City" within three years. Mayor Stephanie Vignal explained the reasoning to the Everett Herald: "if we're going to continue to maintain high quality services, high quality parks, the high quality amenities that everyone looks at us for, then we're going to have to figure out a way to diversify that income stream."
So the City's case to current residents is about spreading costs. Its FAQ says the new revenue would maintain service levels "reducing the need for higher taxes" and would, over time, spread the cost of large capital projects across more properties. Its case to the annexed area is about city services and a vote on the seven-member City Council. The two cases fit together. They just weigh the same dollars differently. The council vote on October 13 was 6–0, and Councilmember Vince Cavaleri abstained. The Herald reported that he did not believe the projections fully account for larger financial trends, including the housing market.
The line that would move
The homes in the proposed area are in unincorporated Snohomish County, inside the City's Urban Growth Area, and are not yet part of the city. The City describes the proposed boundary this way: "35th Avenue down to 180th, following 22nd Dr SE to 192nd St SE, up Waxen Rd to 183rd St SE into Mill Creek." The council packet calls the area Blocks C, D and H, a section that reaches south along the Hwy 527 corridor to 192nd Street SE and includes North Creek Park and Mays Pond Park. The City's annexation map shows the boundary parcel by parcel, so check it before relying on any street-level description.
The change would be large. The Herald reported that the area's estimated 11,700 residents equal more than half of Mill Creek's current population of about 21,000. If the annexation goes through, it would be the City's first since 2008. The Council also considered a larger option that added Blocks A and B to the east. It set that option aside partly because it would have doubled the City's population at once. According to the Herald, the Council has said it is interested in annexing the eastern growth area, toward Sunset Road and east of Seattle Hill Road, within the next three to five years. Buyers there should expect the same questions on a later schedule.
Who decides, and on what calendar
The October vote authorized the City Manager to pursue annexation. It did not change the boundary. The City's planning timeline runs as follows:
- Q4 2026: implementation planning and a project plan, which goes to the Council in December.
- December 2026: the Council decides whether to pursue annexation by a public vote or through an interlocal agreement with Snohomish County.
- Q4 2026 through Q3 2027: community outreach, plus work with the County and the Boundary Review Board.
- November 2027: final filings with the County.
- January 1, 2028: the City's estimated effective date.
The December decision on method also decides whether residents of the area get a direct vote. Under the election route in RCW 35A.14.080, annexation passes with a majority of votes cast. If the City asks the area to assume part of its debt, that question goes on the ballot separately and needs three-fifths approval and turnout of at least 40% of the area's vote in the last general election. The interlocal agreement route under RCW 35A.14.296 works through public hearings and published notice. Annexation then takes effect by ordinance, and residents don't vote. Under that statute, a fire, water-sewer or transportation benefit district that receives notice can ask to join the agreement in time, and once it has done so, its refusal to approve can block the route. A separate interlocal route, RCW 35A.14.470, allows a 45-day referendum period. A petition signed by at least 15% of the votes cast in the area's last general election sends the question to a vote.
The Snohomish County Boundary Review Board comes next. Under RCW 36.93.100, review can be requested within 45 days of filing, including by petition from 5% of the area's voters or from owners of 5% of its assessed value. If someone requests review, the Board has 120 days to decide unless the proponent agrees to more time. The City's consultants expect each stage of Board review to take six to 12 months. That is why January 1, 2028 is an estimate and not a set date.
What this means if you're buying or selling in Mill Creek South
The tax figures are the most settled part of the proposal. The rest of what affects daily ownership is still in planning. The City's FAQ says only that "there are some differences between Mill Creek code and County code" and asks residents to send specific questions. The council packet's list of "issues to watch" says the area spans different fire districts, and it lists open questions about fish passage and water maintenance at North Creek Park and Mays Pond Park.
For a buyer, that suggests a few questions to raise during due diligence:
- Code and zoning: If you plan to add on, build an accessory dwelling or subdivide, ask whether your plans depend on County rules that may differ from Mill Creek's.
- Utilities: Ask how the 5% utility tax would apply to your own utility bills, using the City's $327 to $423 estimate as a starting point.
- Timing: A purchase closing in 2027 could fall during the Boundary Review Board stage, so watch the City's annexation page for updates.
- Debt question: If the Council chooses the election method, find out whether the ballot will include a separate question on assuming City debt.
For sellers in the area, the City's own explanation answers the most common buyer question. The FAQ states that property owners would not have to join a homeowners association because of annexation.
This post is general information about a public process, not legal, tax or financial advice. Please check how annexation would affect your own property with an attorney, tax professional or the City directly.
The City scheduled a community town hall for Tuesday, November 17, from 6:00 to 7:30 p.m. at the Jackson High School library, 1508 136th St. SE. The City's annexation page has the map, links to past council meeting videos and a feedback form for questions about specific properties.
If you own a home between 180th Street SE and 192nd Street SE and want to know how a likely change of city could affect your pricing, timing or buyer questions, Hawkins & O'Bryant can go over it with you before you list. Request your free home valuation and we'll include what the annexation timeline could mean for your sale.
