What Was the 2018 Illinois Primary and When Was It Held
The 2018 Illinois primary was held on Tuesday, March 20, 2018. It determined which candidates advanced to the general election in November. In a presidential election year, statewide turnout is often higher; in 2018, turnout was substantial but typical for a non-presidential primary. The filing deadline for most partisan offices was December 7, 2017. Understanding these dates and the difference between open and closed primaries helps voters know whether they can choose a party ballot on election day or must be registered with that party in advance.
Key 2018 Illinois Primary Dates and Deadlines
Several procedural milestones shaped the 2018 primary. The deadline for candidates to file for ballot access passed in late 2017, and voter registration deadlines followed standard state rules. These dates affect who appears on the ballot and who can vote in the primary. Illinois allows voters to register on Election Day at the polls under certain conditions, but party affiliation must be chosen if a party-specific ballot is requested. Below are the core dates voters relied on to participate.
Important Dates at a Glance
| Date | Event | Why It Matters |
|---|---|---|
| December 7, 2017 | Candidate filing deadline for most offices | Determines which candidates appear on the ballot |
| January 31, 2018 | Voter registration deadline for primary (standard) | Ensures eligibility to vote in the March primary |
| February 5, 2018 | Online and mail registration deadline (National Mail) | Last day for many to register by mail to vote March 20 |
| March 20, 2018 | Primary election day | Ballots cast; winners advance to November general |
| April 2018 | General election filing period begins | Candidates for November ballot file after primary |
What Races Were on the Illinois Primary Ballot in 2018
Illinois ballots in March 2018 included several contested statewide and legislative primaries. Federal offices such as U.S. Senate and U.S. House were contested in each district with competitive primaries. State-level offices, including governor/lieutenant governor and attorney general, appeared where incumbents faced opponents. Legislative primaries determined party nominees for the Illinois House and Senate. Judicial retention questions may also have appeared depending on the circuit. Voters should focus on their district and county for exact contests.
Sample Race Categories on the 2018 Primary Ballot
- U.S. Senate (if contested in the party)
- U.S. House (all Illinois districts)
- Governor / Lieutenant Governor (if contested)
- Attorney General, Secretary of State, Comptroller, Treasurer
- Illinois House and Senate districts
- Judicial retention and local offices by county
How to Read the Illinois Primary Ballot Layout
Illinois ballots group candidates by office and party when a primary is contested. For partisan offices, each party’s candidates appear together, often with a column for party preference and another for choosing a nominee. Ballot order is determined by a rotation designed to spread name visibility fairly across the ballot. Understanding how offices are arranged helps voters locate races quickly and avoid undervoting or overvoting. Marking contests clearly and reviewing instructions at the polling place reduce errors.
Tips for Navigating the Ballot
- Bring a sample ballot or know your wards and districts beforehand
- Check your precinct location and hours in advance
- Review both party columns if you may split-ticket
- Ask poll workers for clarification if a race is unclear
- Use the contest number to find your office quickly on long ballots
Who Could Vote in the 2018 Illinois Primary
To participate in the March 2018 primary, Illinois voters had to meet residency and registration requirements. A valid ID was not required to cast a ballot for most voters, but first-time voters who registered by mail without providing ID documentation might need to show identification. Party affiliation could determine ballot access in closed primaries for certain offices, though Illinois generally allows voters to choose a party ballot at the polls. Voters who were inactive or whose registrations had lapses were urged to verify eligibility before arrival.
Voter Eligibility Checklist
- Be a U.S. citizen and Illinois resident
- Be at least 18 years old on or before election day
- Be registered to vote for the party primary you wish to participate in (rules vary by office)
- Not be serving a felony sentence or under legal guardianship that disenfranchises voting
- Poll location open on Election Day
Where and How to Cast Your 2018 Primary Ballot
Illinois voters cast ballots at their assigned polling place on March 20, 2018, typically open from 6:00 AM to 7:00 PM local time. Early voting and vote-by-mail options were available for those who qualified, though the March primary was largely decided on Election Day. Voters should confirm their polling location in advance, check ID requirements, and review their sample ballot to make informed choices. Drop boxes for absentee ballots closed before Election Day; late submissions were not accepted for the primary.