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2026 US midterm elections — House control

Republican Party controls the House. Listed on both Kalshi and Polymarket; recorded continuously since Aug 9, 2026. Live.

kalshi
10.5¢
bid 0.1 · ask 0.11 · Sep 19, 5:49 AM ET
polymarket
10.5¢
bid 0.1 · ask 0.11 · Sep 19, 5:37 AM ET

Current gap between the two mids: 0.0¢. Over the last 7 days the two venues differed by 0.6% on average and 2.0% at most.

Price history, both venues (7 days)

kalshipolymarket
10.0%10.5%11.0%11.5%12.0%10:2018:0801:5609:45kalshipolymarket
Data table
time (UTC)kalshi midpolymarket mid
Sep 18 10:2011.5%10.5%
Sep 18 10:2511.5%10.5%
Sep 18 10:3010.5%10.5%
Sep 18 10:3510.5%10.5%
Sep 18 10:4010.5%10.5%
Sep 18 10:4510.5%10.5%
Sep 18 10:5010.5%10.5%
Sep 18 10:5510.5%10.5%
Sep 18 11:0010.5%10.5%
Sep 18 11:0510.5%10.5%
Sep 18 11:1010.5%10.5%
Sep 18 11:1510.5%10.5%
Sep 18 11:2010.5%10.5%
Sep 18 11:2510.5%10.5%
Sep 18 11:3010.5%10.5%
Sep 18 11:3510.5%10.5%
Sep 18 11:4010.5%10.5%
Sep 18 11:4510.5%10.5%
Sep 18 11:5010.5%10.5%
Sep 18 11:5510.5%10.5%
Sep 18 12:0010.5%10.5%
Sep 18 12:0510.5%10.5%
Sep 18 12:1010.5%10.5%
Sep 18 12:1510.5%10.5%
Sep 18 12:2010.5%10.5%
Sep 18 12:2510.5%10.5%
Sep 18 12:3010.5%10.5%
Sep 18 12:3510.5%10.5%
Sep 18 12:4010.5%10.5%
Sep 18 12:4510.5%10.5%
Sep 18 12:5010.5%10.5%
Sep 18 12:5510.5%10.5%
Sep 18 13:0010.5%10.5%
Sep 18 13:0510.5%10.5%
Sep 18 13:1010.5%10.5%
Sep 18 13:1510.5%10.5%
Sep 18 13:2010.5%10.5%
Sep 18 13:2510.5%10.5%
Sep 18 13:3010.5%10.5%
Sep 18 13:3510.5%10.5%
Sep 18 13:4010.5%10.5%
Sep 18 13:4510.5%10.5%
Sep 18 13:5010.5%
Sep 18 13:5510.5%
Sep 18 14:0010.5%
Sep 18 14:0510.5%
Sep 18 14:1010.5%
Sep 18 14:1510.5%
Sep 18 14:2010.5%
Sep 18 14:2510.5%
Sep 18 14:3010.5%
Sep 18 14:3510.5%
Sep 18 14:4010.5%
Sep 18 14:4510.5%
Sep 18 14:5010.5%
Sep 18 14:5510.5%
Sep 18 15:0010.5%
Sep 18 15:0510.5%
Sep 18 15:1010.5%
Sep 18 15:1510.5%
Sep 18 15:2010.5%
Sep 18 15:2510.5%
Sep 18 15:3010.5%
Sep 18 15:3510.5%
Sep 18 15:4010.5%
Sep 18 15:4510.5%
Sep 18 15:5010.5%
Sep 18 15:5510.5%
Sep 18 16:0010.5%
Sep 18 16:0510.5%
Sep 18 16:1010.5%
Sep 18 16:1510.5%
Sep 18 16:2010.5%
Sep 18 16:2510.5%
Sep 18 16:3010.5%
Sep 18 16:3510.5%
Sep 18 16:4010.5%
Sep 18 16:4510.5%
Sep 18 16:5010.5%
Sep 18 16:5510.5%
Sep 18 17:0010.5%
Sep 18 17:0510.5%
Sep 18 17:1010.5%
Sep 18 17:1510.5%
Sep 18 17:2010.5%
Sep 18 17:2510.5%
Sep 18 17:3010.5%
Sep 18 17:3510.5%
Sep 18 17:4010.5%
Sep 18 17:4510.5%
Sep 18 17:5010.5%
Sep 18 17:5510.5%
Sep 18 18:0010.5%
Sep 18 18:0510.5%
Sep 18 18:1010.5%
Sep 18 18:1510.5%
Sep 18 18:2010.5%
Sep 18 18:2510.5%
Sep 18 18:3010.5%
Sep 18 18:3510.5%
Sep 18 18:4010.5%
Sep 18 18:4510.5%
Sep 18 18:5010.5%
Sep 18 18:5510.5%
Sep 18 19:0010.5%
Sep 18 19:0510.5%
Sep 18 19:1010.5%
Sep 18 19:1510.5%
Sep 18 19:2010.5%
Sep 18 19:2510.5%
Sep 18 19:3010.5%
Sep 18 19:3510.5%
Sep 18 19:4010.5%
Sep 18 19:4510.5%
Sep 18 19:5010.5%
Sep 18 19:5510.5%
Sep 18 20:0010.5%
Sep 18 20:0510.5%
Sep 18 20:1010.5%
Sep 18 20:1510.5%
Sep 18 20:2010.5%
Sep 18 20:2510.5%
Sep 18 20:3010.5%
Sep 18 20:3510.5%
Sep 18 20:4010.5%
Sep 18 20:4510.5%
Sep 18 20:5010.5%
Sep 18 20:5510.5%
Sep 18 21:0010.5%
Sep 18 21:0510.5%
Sep 18 21:1010.5%
Sep 18 21:1510.5%
Sep 18 21:2010.5%
Sep 18 21:2510.5%
Sep 18 21:3010.5%
Sep 18 21:3510.5%
Sep 18 21:4010.5%
Sep 18 21:4510.5%
Sep 18 21:5010.5%
Sep 18 21:5510.5%
Sep 18 22:0010.5%
Sep 18 22:0510.5%
Sep 18 22:1010.5%
Sep 18 22:1510.5%
Sep 18 22:2010.5%
Sep 18 22:2510.5%
Sep 18 22:3010.5%
Sep 18 22:3510.5%
Sep 18 22:4010.5%
Sep 18 22:4510.5%
Sep 18 22:5010.5%
Sep 18 22:5510.5%
Sep 18 23:0010.5%
Sep 18 23:0510.5%
Sep 18 23:1010.5%
Sep 18 23:1510.5%
Sep 18 23:2010.5%
Sep 18 23:2510.5%
Sep 18 23:3010.5%
Sep 18 23:3510.5%
Sep 18 23:4010.5%
Sep 18 23:4510.5%
Sep 18 23:5010.5%
Sep 18 23:5510.5%
Sep 19 00:0010.5%
Sep 19 00:0510.5%
Sep 19 00:1010.5%
Sep 19 00:1510.5%
Sep 19 00:2010.5%
Sep 19 00:2510.5%
Sep 19 00:3010.5%
Sep 19 00:3510.5%
Sep 19 00:4010.5%
Sep 19 00:4510.5%
Sep 19 00:5010.5%
Sep 19 00:5510.5%
Sep 19 01:0010.5%
Sep 19 01:0510.5%
Sep 19 01:1010.5%
Sep 19 01:1510.5%
Sep 19 01:2010.5%
Sep 19 01:2510.5%
Sep 19 01:3010.5%
Sep 19 01:3510.5%
Sep 19 01:4010.5%
Sep 19 01:4510.5%
Sep 19 01:5010.5%
Sep 19 01:5510.5%
Sep 19 02:0010.5%
Sep 19 02:0510.5%
Sep 19 02:1010.5%
Sep 19 02:1510.5%
Sep 19 02:2010.5%
Sep 19 02:2510.5%
Sep 19 02:3010.5%
Sep 19 02:3510.5%
Sep 19 02:4010.5%
Sep 19 02:4510.5%
Sep 19 02:5010.5%
Sep 19 02:5510.5%
Sep 19 03:0010.5%
Sep 19 03:0510.5%
Sep 19 03:1010.5%
Sep 19 03:1510.5%
Sep 19 03:2010.5%
Sep 19 03:2510.5%
Sep 19 03:3010.5%
Sep 19 03:3510.5%
Sep 19 03:4010.5%
Sep 19 03:4510.5%
Sep 19 03:5010.5%
Sep 19 03:5510.5%
Sep 19 04:0010.5%
Sep 19 04:0510.5%
Sep 19 04:1010.5%
Sep 19 04:1510.5%
Sep 19 04:2010.5%
Sep 19 04:2510.5%
Sep 19 04:3010.5%
Sep 19 04:3510.5%
Sep 19 04:4010.5%
Sep 19 04:4510.5%
Sep 19 04:5010.5%
Sep 19 04:5510.5%
Sep 19 05:0010.5%
Sep 19 05:0510.5%
Sep 19 05:1010.5%
Sep 19 05:1510.5%
Sep 19 05:2010.5%
Sep 19 05:2510.5%
Sep 19 05:3010.5%
Sep 19 05:3510.5%
Sep 19 05:4010.5%
Sep 19 05:4510.5%
Sep 19 05:5010.5%
Sep 19 05:5510.5%
Sep 19 06:0010.5%
Sep 19 06:0510.5%
Sep 19 06:1010.5%
Sep 19 06:1510.5%
Sep 19 06:2010.5%
Sep 19 06:2510.5%
Sep 19 06:3010.5%
Sep 19 06:3510.5%
Sep 19 06:4010.5%
Sep 19 06:4510.5%
Sep 19 06:5010.5%
Sep 19 06:5510.5%
Sep 19 07:0010.5%
Sep 19 07:0510.5%
Sep 19 07:1010.5%
Sep 19 07:1510.5%
Sep 19 07:2010.5%
Sep 19 07:2510.5%
Sep 19 07:3010.5%
Sep 19 07:3510.5%
Sep 19 07:4010.5%
Sep 19 07:4510.5%
Sep 19 07:5010.5%
Sep 19 07:5510.5%
Sep 19 08:0010.5%
Sep 19 08:0510.5%
Sep 19 08:1010.5%
Sep 19 08:1510.5%
Sep 19 08:2010.5%
Sep 19 08:2510.5%
Sep 19 08:3010.5%
Sep 19 08:3510.5%
Sep 19 08:4010.5%
Sep 19 08:4510.5%
Sep 19 08:5010.5%
Sep 19 08:5510.5%
Sep 19 09:0010.5%
Sep 19 09:0510.5%
Sep 19 09:1010.5%
Sep 19 09:1510.5%
Sep 19 09:2010.5%
Sep 19 09:2510.5%
Sep 19 09:3010.5%
Sep 19 09:3510.5%
Sep 19 09:4010.5%
Sep 19 09:4510.5%

Mid price of the YES side per venue, 5-minute buckets, from continuously recorded order books. Breaks mean the recorder was down or a book was empty.

Disagreement windows
24
beyond fees, at size
Largest net edge
1.71%
avg 0.87%
Typical window
719 min
longest 4090 min
Last window
Sep 8, 2026
first Aug 9, 2026

Recent disagreement windows

OpenedClosedLengthScansMax net edge
Sep 8, 12:15 AM ETSep 8, 9:40 AM ET9.4 h7830.58%
Sep 2, 1:34 PM ETSep 2, 1:38 PM ET4 min71.71%
Aug 30, 10:16 PM ETSep 2, 12:31 PM ET62.3 h3,0341.71%
Aug 26, 10:32 AM ETAug 28, 10:14 AM ET47.7 h2,5171.71%
Aug 26, 2:30 AM ETAug 26, 2:30 AM ET0 min10.66%
Aug 25, 5:35 PM ETAug 25, 9:47 PM ET4.2 h2510.66%
Aug 25, 3:59 AM ETAug 25, 7:54 AM ET3.9 h2670.66%
Aug 24, 9:29 PM ETAug 24, 9:30 PM ET1 min30.66%
Aug 24, 3:41 PM ETAug 24, 8:00 PM ET4.3 h2280.66%
Aug 23, 8:49 AM ETAug 24, 2:34 PM ET29.7 h1,6490.74%

Frequently asked questions

What are the current Kalshi and Polymarket odds for "2026 US midterm elections — House control"?

As of the latest recorded books, Kalshi's YES mid is 10.5¢ (bid 0.1, ask 0.11) and Polymarket's is 10.5¢ (bid 0.1, ask 0.11) — a 0.0¢ gap. Prices are recorded continuously; this page refreshes every few minutes.

Has this market been an arbitrage?

Yes — 24 separate windows where buying the cheaper side on each venue cost less than $1 after both fees, first on Aug 9, 2026 and most recently Sep 8, 2026. The largest net edge was 1.71% and windows averaged 719 minutes.

Do both contracts resolve the same way?

The pair was confirmed as the same question (human-reviewed). That judgment covers the headline question; resolution rules can still differ in edge cases (sources, timing, ties). Read both venues' rules before treating a gap as risk-free.

What do the fees do to the gap?

Kalshi charges takers 7% × price × (1 − price) per contract; Polymarket charges its category rate on the same curve. Near 50¢ that is roughly 1.75¢ per contract on Kalshi and 1–1.75¢ on Polymarket, so a visible gap of 3–4¢ is typically the minimum before anything is left.

← every Kalshi↔Polymarket pair · resolution criteria · taker fees · match: human-reviewed. Verify both markets' rules yourself; this is data, not advice.