# Will any country leave NATO by...

> Liquidity-weighted aggregate at 6% across 1 contract — refreshed 31 min ago.

URL: https://simplefunctions.dev/odds/any-country-leave-nato
Updated: 2026-06-08T07:20:11.808Z
Category: geopolitics · Topic: ukraine
Status: active
Closes: 2026-12-31

## Headline

- Probability: 6% (liquidity-weighted across 1 contract)
- Venue: Polymarket (1 contract)
- 24h volume: $26

## Bound contracts (1)

| Outcome | Price | 24h | Volume | Venue | Slug |
|---|---|---|---|---|---|
| December 31, 2026 | 6¢ | ±0 | $26 | polymarket | /markets/will-any-country-leave-nato-by-december-31-2026-polymarket-0x523959b6256674318eb34755789fffd8c62cd652e5fa11ffd332402361d058e9 |

## 30-day trajectory

| Day | Aggregate |
|---|---|
| 2026-05-09 | 7 |
| 2026-05-19 | 8 |
| 2026-06-01 | 7 |
| 2026-06-06 | 6 |

_9 days of price history captured. Each row is the daily mean of intraday 5-min captures._

## Analysis

This probability estimates the chance that at least one NATO member country will withdraw from the alliance by a specified date. The 13% aggregate reflects significant uncertainty, with notable disagreement between venues: Kalshi prices in substantially higher withdrawal risk (24%) compared to Polymarket (9%). The gap likely reflects differing assessments of US political developments, particularly around potential policy shifts toward NATO commitments. Factors pushing probability upward include geopolitical tensions, domestic political changes in member states, and shifts in alliance burden-sharing debates. Factors pushing downward include institutional inertia, economic interdependence, and the high costs of NATO exit. The most immediate driver is US election and policy outcomes, given that a US withdrawal would constitute the likeliest scenario priced into these contracts.

### Key factors

- US domestic political positions on NATO funding and alliance commitments will directly shape withdrawal likelihood given America's outsized role
- Kalshi-Polymarket divergence (15 percentage points) suggests traders weight geopolitical risks and political change probabilities differently across platforms
- Polymarket contracts show lowest probabilities on near-term US withdrawal (3-12¢ for mid-2026), indicating markets view full exit as unlikely within 18 months
- Historical NATO membership has shown high persistence despite periodic political friction and burden-sharing disputes
- Specific triggering events (major military conflict, allied security guarantee withdrawal, formal treaty revision) rather than gradual drift would most likely precipitate withdrawal

## Methodology

Probability is **liquidity-weighted** across all bound Kalshi/Polymarket contracts: Σ(price × volume) ÷ Σ(volume). 30-day trajectory uses the daily mean of intraday 5-min captures. 24h delta = today's mean − yesterday's mean. Movement events are ≥3pp daily moves in the last 7 days.

## How to use this data

- HTML: https://simplefunctions.dev/odds/any-country-leave-nato
- JSON: https://simplefunctions.dev/api/public/odds?slug=any-country-leave-nato
- Topic hub: https://simplefunctions.dev/predictions/ukraine

## License

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