Midterms 2026Answers · Midterms
How many House and Senate seats are up in the 2026 midterms?
All 435 House seats are up in 2026, plus 35 of the 100 Senate seats. The Senate number includes special elections held to fill terms that didn't finish. So 470 voting seats in total are on the ballot on November 3.
Why all of the House, but only part of the Senate
House members serve two-year terms, so the whole chamber faces voters every even-numbered year. That's why every midterm is a full reset for the House.
Senators serve six-year terms, and the terms are staggered into three groups, called classes. Roughly a third of the Senate is up every two years. That's the regular rotation. In 2026, the regular group plus a couple of special elections brings the total to 35.
What the numbers mean for control
For the House, 218 is the majority. Since every seat is up, the entire chamber can change hands in one night.
For the Senate, the picture is more limited. Because only a third is up, control depends on the seats on the ballot plus the seats the parties already hold that aren't up. A party can't win the Senate from a single election if it's far behind in the seats nobody is voting on this year. In a 50-50 Senate, the vice president breaks ties, so the party of the VP gets the edge.
Some other counts to keep in mind:
- 435 voting House members, a number fixed by law since 1929
- 6 non-voting delegates (DC, Puerto Rico and the territories), who also appear on ballots but don't vote on final passage
- 100 senators, two per state
Are all those seats actually competitive?
No. Most House seats lean clearly toward one party, and many Senate races aren't close either. The fights that decide control tend to happen in a smaller group of districts and states. I'd guess that surprises people who assume every race is a toss-up.
You can see this yourself by looking at any map of competitive seats. The shaded close races are always a small slice of the full list.
A way to play with these numbers
I built Midterms 2026, a free iPhone game, around this exact setup. On election night it counts 35 Senate races and all 435 House seats, so the totals in the game mirror the real ballot size. During the 20 weeks of campaigning you can watch the "Senate if the vote was today" and "House if the vote was today" projections, which makes it easier to see how few seats usually decide the outcome. The parties and characters are fictional.
The short version
- 435 House seats and 35 Senate seats are up in 2026
- The House is fully up every two years, the Senate about a third at a time
- A few competitive races usually decide control