Candidates running for McHenry County offices – including several countywide offices, half the County Board and precinct committeepeople – can file petitions at the county building starting Monday. Here’s what to know.

What offices are up?

Four countywide offices and half the seats on the County Board are up in next year’s election, for which the primary is March 17. All of the countywide incumbents are Republicans, as are seven of the nine County Board members seeking reelection. The GOP has a 15-3 supermajority on the board. The countywide positions on the ballot – all held by incumbents seeking reelection – are:

• sheriff; incumbent Robb Tadelman
• treasurer; incumbent Donna Kurtz
• clerk-recorder; incumbent Joe Tirio
• regional superintendent of schools; incumbent Diana Hartmann

What about the County Board?

Nine of the board’s 18 seats will be on the ballot next year, and all those incumbents also have said they’ll run for reelection. Here’s a look at their districts:

• District 1 is based in southeastern McHenry County and includes all or parts of Algonquin, Fox River Grove, Cary, Barrington Hills and Trout Valley. The incumbent up for reelection is Matt Kunkle, R-Algonquin.
• District 2 is based in southeastern McHenry County and includes all or parts of Crystal Lake, Cary, Lake in the Hills, Algonquin and Lakewood. Gloria Van Hof, D-Crystal Lake, holds the seat on the ballot next year.
• District 3 is in south-central McHenry County and includes all or parts of Lake in the Hills, Algonquin, Crystal Lake, Huntley and Lakewood. The incumbent is Carolyn Campbell, D-Crystal Lake.
• District 4 is in central McHenry County and covers all or parts of Crystal Lake, Cary, Bull Valley, Woodstock, McHenry and Prairie Grove. Joe Gottemoller, R-Crystal Lake, holds the seat that’s up for election.
• District 5 is in eastern McHenry County and covers all or parts of McHenry, Prairie Grove, Cary, Lakemoor, Island Lake, Port Barrington, Oakwood Hills and Holiday Hills. The incumbent up for reelection is Terri Greeno, R-Crystal Lake.
• District 6 is in northeastern McHenry County and includes all or parts of McHenry, Johnsburg, Spring Grove, Fox Lake, Lakemoor and Ringwood. Pamela Althoff, R-McHenry, holds the seat.
• District 7 is in central McHenry County and includes all or parts of Woodstock, McHenry, Wonder Lake, Bull Valley and Greenwood. The incumbent is Brian Sager, R-Woodstock.
• District 8 stretches across a large swath of northern and western McHenry County and includes all or parts of Harvard, Hebron, Richmond, Woodstock, Marengo and Spring Grove. Larry Smith, R-Harvard, is the incumbent up for reelection.
• District 9 is in southwestern McHenry County and includes all or parts of Marengo, Huntley, Lake in the Hills, Algonquin and Union. Michael Skala, R-Huntley, holds the post.