The short version.
Yolo County, CA has 122,711 active registered voters — 20.3% Republican, 50.0% Democratic, and 23.0% with no party affiliation, as of October 2026.
California puts your county elections office at the centre of everything, even for state offices. Whatever you are running for, you collect your nomination papers from, and file them with, the elections official in the county where you live. There is no separate state filing counter to visit.
The other thing to know is that California runs a top-two primary. Every candidate for most offices appears on one primary ballot open to all voters, and the two highest finishers go to November regardless of party. Coming second in the primary is not losing.
This page covers that for Yolo County and points you at your local election office for anything specific to your county. It is not legal advice; the official rules live with your election office and the California Secretary of State.
Yolo County by the numbers.
- 122,711 active registered voters across 388 precincts (official California voter file, October 2026).
- Party registration: Democratic 50.0% · Republican 20.3% · no party affiliation 23.0% · other parties 6.7%.
- 64,575 supervoters (52.62%, voted in at least 3 of the last 4 November generals). These are the doors reliable-voter campaigns knock first.
- In 2024, Yolo County cast 92,589 votes for president: 30.1% Republican, 66.3% Democratic.
Full statistics, party breakdown and turnout history: Yolo County voter data.
The campaigns that win the field are the ones who start building their list of supporters and volunteers before qualifying even opens, not after. The California voter file is already loaded in Motion51, so you can start finding your people today.
Key California dates.
Write-in filing for the November 3, 2026 ballot, September 7 to October 20, 2026
The regular nomination period closed at 5:00 p.m. on August 7, 2026, and the five-day extension for non-incumbents closed on August 12, 2026. The write-in filing window for the November 3, 2026 ballot runs from Monday, September 7, 2026 to 5:00 p.m. on Tuesday, October 20, 2026.
- Mon Sep 7 to Tue Oct 20, 2026, 5:00 p.m. STILL OPEN. WRITE-IN CANDIDACY. File a Statement of Write-In Candidacy plus nomination papers with your county elections official (Elec. Code secs. 8600, 8601). For a single-county or sub-county office that is 20 to 40 registered-voter signatures from inside the district (sec. 8062(a)(3)), and there is no filing fee except for city offices.
- Fri Oct 23, 2026 The certified list of qualified write-in candidates is published. Votes are counted only for names on it: sec. 15341 says no name written on a ballot counts unless that person complied with the write-in filing rules. An unregistered write-in campaign produces nothing countable.
- Fri Aug 7, 2026, 5:00 p.m. CLOSED. Regular nomination period -- CLOSED (sec. 8020(b)).
- Wed Aug 12, 2026, 5:00 p.m. CLOSED. Five-day extension where an incumbent did not file -- CLOSED, and it never applied to a seat with no eligible incumbent (secs. 8022, 8024).
- Fri Aug 7, 2026, 5:00 p.m. CLOSED. Independent nomination papers -- CLOSED (sec. 8403, the 88th day before the election).
In California the June primary IS the election for most county offices. Sec. 8140 says a candidate who wins a majority of all ballots cast for that office at the primary is elected outright, and the office then does not appear on the November ballot at all. Most supervisor, assessor and clerk races are simply over in June, decided by a low-turnout electorate. Plan around November and you have already missed everything.
2028, the next time county office is on the ballot
District attorney and sheriff run on the presidential cycle; the rest of the county courthouse does not. Assessor, auditor, clerk-recorder, treasurer-tax collector and county superintendent of schools ride the gubernatorial primary under sec. 1201, so they were last up in June 2026 and are next up in June 2030. Board of Supervisors seats are staggered and some are up every even year.
- Mon Nov 15 to Fri Dec 10, 2027, 5:00 p.m. COMPUTED nomination window for the March 2028 primary. Sec. 8020(b) makes documents available on the 113th day before the election and due at 5:00 p.m. on the 88th.
- Mon Jan 10 to Tue Feb 22, 2028, 5:00 p.m. COMPUTED write-in window for the primary, the 57th to the 14th day before (sec. 8601).
- Tue Mar 7, 2028 PRESIDENTIAL PRIMARY, published by the Secretary of State. District attorney and sheriff are elected here (sec. 1300(a)(1)).
- Mon Jul 17 to Fri Aug 11, 2028, 5:00 p.m. COMPUTED nomination window for the November ballot: school district, community college and special district seats (secs. 8020(b), 10510).
- Tue Nov 7, 2028 PRESIDENTIAL GENERAL, published. Runoffs for any county office nobody won outright in March, plus most district seats.
Which Board of Supervisors districts are up in 2028 varies county by county, and a charter county can put other officers on a different cycle under sec. 1300(b)(2). Confirm your own seat with your county elections official before you plan around any of this.
Status as of October 18, 2026: dates that have passed are greyed out and marked CLOSED.
The 2026 dates come from the California Secretary of State's November 3, 2026 general election calendar and key-dates page, checked on 2026-08-20. California has published no 2028 candidate calendar, so the 2028 filing dates below are arithmetic from the Elections Code. Confirm any date you plan to rely on with your county elections official.
The 2027 ballot in Yolo County.
These 2027 dates are confirmed against the state's own published calendar or statute. Anything our research could not confirm is left off this page rather than estimated.
-
November 2, 2027
Nonpartisan — Mixed.
Which local offices are on this ballot varies by jurisdiction; the Yolo County Assessor/Clerk-Recorder/Registrar of Voters can tell you which of yours is.
Candidate filing: opens Jul 12, 2027, closes Aug 6, 2027.
Source 1 · Source 2
2027 dates can move, and a municipality can change its own election date by ordinance. Which seats are on a given ballot depends on when each was last filled. Confirm anything you are relying on with the Yolo County Assessor/Clerk-Recorder/Registrar of Voters before you act on it.
Offices on the ballot in Yolo County.
California county offices are elected on four-year terms, usually at the statewide primary rather than in November, and often on a stagger so that only some seats appear in any given cycle. These are the county seats that commonly appear:
- County Supervisor, on the Board of Supervisors — usually staggered, so only some districts each cycle
- Sheriff, or Sheriff-Coroner where the county combines the two
- District Attorney
- Assessor
- Auditor-Controller, County Clerk-Recorder, and Treasurer-Tax Collector — many California counties combine several of these into one elected post
- Superintendent of Schools, and county board of education seats
- Statewide and legislative seats on the same 2026 ballot: Governor, Lieutenant Governor, Attorney General, Secretary of State, Controller, Treasurer, Insurance Commissioner, Superintendent of Public Instruction, all 52 U.S. House seats, the entire Assembly (80 seats) and the even-numbered State Senate districts (20 seats)
Which county offices are elected, and which are combined or appointed, varies more in California than in most states. Your county elections office holds the definitive list for your county.
How to get on the ballot.
Two things get you onto the ballot: nomination papers signed by a small number of registered voters, and either a filing fee or signatures collected in place of it. Both are handled by your county elections official.
Everything goes through your county elections office.
This is the part that surprises people. Even a candidate for the Assembly or Congress obtains their Declaration of Candidacy and nomination papers from the county elections official where they live, and files them there. The office named on this page is that office for this county.
- Nomination documents are obtained and filed between E-113 and E-88 — a four-week window ending at 5:00 p.m.
- In-lieu-of-fee petition sections are filed with the county elections official of the county where each signer lives.
- The forms are free. You are never charged for the paperwork itself.
If the sitting officeholder does not file by the deadline, the window reopens for five more days for everyone else. That is how a seat that looked settled suddenly becomes a real race.
Option 1: Pay the filing fee.
California sets the fee as a percentage of the first year's salary of the office, so it scales with the job rather than being a flat charge:
- Statewide offices and U.S. Senator: 2% of the first year's salary.
- U.S. Representative, State Senator and Member of the Assembly: 1%. For 2026 that made an Assembly seat $1,346.94.
- County and local offices set their own fees locally, so the amount differs from county to county — ask your county elections office.
- Write-in candidates pay no filing fee at all.
The fee is due when you collect your nomination papers, not later, so work out the amount before you walk in.
Option 2: Signatures in lieu of the filing fee.
You can replace the fee, in whole or in part, with signatures from registered voters. This is genuinely useful and under-used: each valid signature is worth a set amount off the fee, and you can pay the difference if you fall short.
- For an Assembly seat in 2026 the requirement was 857 valid signatures, each worth about $1.57 against the fee.
- You may submit signatures covering any prorated portion of the fee and simply pay the rest.
- Signatures collected on an in-lieu petition can also count toward the nomination-paper requirement, so the work is not duplicated.
- For county and local offices the count is set against that office's own fee — your elections office will tell you the number.
The in-lieu window closes two weeks before the nomination period even opens, which catches people out. If you might use this route, start in December.
Nomination papers, which everyone files.
Separately from the fee, every candidate files nomination papers carrying a small number of signatures from registered voters in the district.
- 40 to 60 signatures for U.S. Representative, State Senator or Member of the Assembly.
- 65 to 100 for statewide office or U.S. Senator.
- There is a maximum as well as a minimum. You can sign and circulate your own papers.
Statutory references: Cal. Elec. Code 8020-8028 (nomination period) · Cal. Elec. Code 8103, 8105 (filing fees) · Cal. Elec. Code 8106, 8162 (signatures in lieu) · Cal. Elec. Code 8061-8068 (nomination papers). Fees and signature counts change; confirm before you file.
The Yolo County Assessor/Clerk-Recorder/Registrar of Voters.
In California this office does everything: it issues your nomination papers, takes your filing fee or in-lieu signatures, and runs the election. It is also who to ask about which districts you live in and which seats are up.
- Office
- 625 Court Street, Room B-05, Woodland, CA 95695
- Phone
- (530) 666-8133
Contact details verified 2026-08-11. Official statewide sources: California SOS — running for office in 2026 · County elections offices directory · California Secretary of State — Elections.
Common questions.
When is the filing deadline for office in Yolo County?
For the 2026 cycle the nomination period ran from February 9 to 5:00 p.m. on March 6, 2026, filed with the Yolo County elections office. That has closed. California repeats the same pattern each cycle — nomination papers roughly four months before the primary, and in-lieu-of-fee petitions from the previous December — so if you are planning for the next cycle in Yolo County, December is when it really starts.
How much does it cost to run for office in Yolo County?
It depends on the office. California sets the fee as a share of the first year's salary — 1% for legislative and congressional seats, 2% for statewide offices. For scale, an Assembly seat in 2026 was $1,346.94. County and local offices in Yolo County set their fees locally, so ask the elections office named on this page. You can also replace the fee entirely with signatures from registered voters.
Can I run for office in Yolo County without paying the filing fee?
Yes. California lets you collect signatures in lieu of the fee, and each valid signature is worth a fixed amount against it — for an Assembly seat in 2026, 857 signatures covered the whole fee at about $1.57 each. You can cover part of the fee with signatures and pay the rest. The catch is timing: that petition window closes before the nomination period opens, so it has to be planned months ahead.
Where is the Yolo County elections office?
It is named on this page with its address, phone number and website. In California this is the office you deal with for everything, including running for state or congressional office — nomination papers are always issued and filed in the county where the candidate lives.
Do I have to win a primary to run for office in Yolo County?
For most offices California uses a top-two primary: every candidate appears on one June ballot open to all voters, and the two highest finishers go through to November whatever their party. So finishing second in the primary is not losing. Some county and local offices are decided outright in the primary if a candidate wins a majority.
How many registered voters are in Yolo County?
Yolo County has 122,711 active registered voters across 388 precincts in the official California voter file (October 2026). The full breakdown, and how the county voted in the last presidential election, is at the top of this page.
After you qualify: the field operation.
California races are decided by turnout in a state where almost everyone votes by mail, and where a top-two primary means you may face the same opponent twice. Knowing which of your voters actually return a ballot, and which precincts move, matters more than raw registration numbers.
That is the part Motion51 was built for. You scope your district, cut turf, and send volunteers out with a phone instead of a clipboard. It works offline, so canvassing does not stop where the cell signal does, and every door is logged with a timestamp for your records. Our For Candidates page walks through what that looks like.
Yolo County at a glance.
Yolo County had an estimated 225,251 residents in July 2024, the 27th most populous of California's 58 counties, up 3.4% since the 2020 census. Of those, 181,959 are 18 or older, the voting-age population, and 14.1% are 65 or older. Its 122,711 active registered voters equal about 67.4% of that voting-age population.
It covers 1,013 square miles of land (222 people per square mile), and 13.9% of residents live outside any incorporated city or town. The largest cities and towns are Davis (67,125), Woodland (62,983), West Sacramento (55,991) and Winters (7,825). The American Community Survey (2020-2024) puts it at a median age of 32.1, a median household income of $91,752, 44.8% of adults 25 and older holding a bachelor's degree or higher and 54.3% of occupied homes owned by the people living in them.
In 2024, 92,589 votes were cast for president, about 50.9% of the voting-age population; the Democratic ticket took 66.3% and the Republican ticket 30.1%. The two-party margin moved from D+36.3 in 2008 to D+36.2 in 2024.
- Population (2024 estimate)
- 225,251
- Population (2020 census base)
- 217,867
- Voting-age population (18+)
- 181,959
- Active voters per 100 adults
- 67.4
- Residents 65 and older
- 14.1%
- People per square mile
- 222
- Living outside incorporated places
- 13.9%
- Land area
- 1,013 sq mi
- Median age
- 32.1
- Median household income
- $91,752
- Adults 25+ with a bachelor's degree
- 44.8%
- Owner-occupied homes
- 54.3%
Largest cities and towns
- Davis 67,125
- Woodland 62,983
- West Sacramento 55,991
- Winters 7,825
Presidential vote, 2008–2024
| Year | Democratic | Republican | Margin | Votes cast |
|---|---|---|---|---|
| 2024 | 66.3% | 30.1% | D+36.2 | 92,589 |
| 2020 | 69.5% | 28.1% | D+41.4 | 97,264 |
| 2016 | 68.1% | 26.0% | D+42.1 | 50,623 |
| 2012 | 65.2% | 32.0% | D+33.2 | 59,613 |
| 2008 | 67.1% | 30.8% | D+36.3 | 79,749 |
Sources: U.S. Census Bureau Vintage 2024 population estimates and 2024 Gazetteer; American Community Survey 2020–2024 5-year estimates; certified county presidential returns. Growth, density and turnout are simple arithmetic on those figures.
Counties next to Yolo.
Running in a district that crosses a county line? Each of these has its own guide.