# Will Congress ever override Trump's veto

> Before Jan 20, 2029 leads at 29%, runner-up 10% across 2 winner-take-all outcomes — refreshed 26 min ago.

URL: https://simplefunctions.dev/odds/vetooverride
Updated: 2026-07-09T21:20:50.957Z
Category: general · Topic: trump
Status: active
Closes: 2029-01-20

## Headline

- Leader: Before Jan 20, 2029 at 29%
- Runner-up: Before 2027 at 10%
- Outcomes: 2 (winner-take-all)
- Venue: Kalshi (2 contracts)
- 24h volume: $0

## Bound contracts (2)

| Outcome | Price | 24h | Volume | Venue | Slug |
|---|---|---|---|---|---|
| Before Jan 20, 2029 | 29¢ | ±0 | $0 | kalshi | /markets/will-congress-ever-override-trumps-veto-before-jan-kalshi-kxvetooverride-29jan20 |
| Before 2027 | 10¢ | −3pp | $0 | kalshi | /markets/will-congress-override-trumps-veto-before-2027-bef-kalshi-kxvetooverride-29jan20-27 |

## 30-day trajectory

| Day | Before Jan 20, 2029 | Before 2027 |
|---|---|---|
| 2026-06-09 | — | 5 |
| 2026-06-11 | 26 | 5 |
| 2026-06-25 | 30 | 10 |
| 2026-07-02 | 29 | 13 |
| 2026-07-04 | 29 | 12 |
| 2026-07-08 | — | 10 |

_22 days of price history captured. Each row is the daily mean of intraday 5-min captures._

## What moved the line

- 2026-07-08 · Before 2027 −3pp 13→10¢ · kalshi

## Analysis

This represents the likelihood that Congress will muster a two-thirds majority in both chambers to overturn a Trump veto before January 20, 2029. Veto overrides are historically rare—only about 7% of presidential vetoes are overridden—and require substantial bipartisan consensus. The current 29% probability reflects uncertainty about both the frequency and type of vetoes Trump issues and whether either party will have sufficient motivation to override them. Key drivers include the composition of Congress, the partisan salience of specific bills being vetoed, and whether any vetoes affect widely-supported legislation. The market has priced lower odds for an override before 2027 (10%) compared to the full 2029 window, suggesting traders view the probability as more likely in the latter half of a potential Trump presidency. Major catalysts would include actual vetoes of significant bipartisan bills in the coming months, which would provide concrete test cases for override likelihood.

### Key factors

- Override success requires 67 votes in Senate and 290 in House; current Congress composition affects feasibility
- Historical veto override rate is approximately 7%, providing baseline for how rare these outcomes are
- Type of legislation matters significantly—overrides more likely on widely-popular bills with genuine bipartisan support
- Political polarization affects willingness to cross party lines on major presidential disagreements
- Early vetoes in 2026-2027 would provide direct evidence; their topics and voting patterns would indicate trajectory toward 29% or elsewhere

## Methodology

Headline is the **leader's price**, not an arithmetic mean — averaging disjoint winner-take-all outcomes is meaningless. Per-outcome prices come from the venue's last-traded mid; cross-venue values are simple means across contracts on each venue.

## How to use this data

- HTML: https://simplefunctions.dev/odds/vetooverride
- JSON: https://simplefunctions.dev/api/public/odds?slug=vetooverride
- Topic hub: https://simplefunctions.dev/predictions/trump

## License

CC-BY-4.0. Attribute "SimpleFunctions" with a link to https://simplefunctions.dev. See https://simplefunctions.dev/legal for terms.