GPT-5.6 released on 2026?

Platform comparison

Market context

OpenAI has officially announced the GPT‑5.6 family on 26 June 2026, yet a full public launch has been deferred at the US government’s request, limiting initial access to a small group of vetted partners and excluding ChatGPT users during the preview phase[3][6]. While the preview system card states broader availability is planned in the coming weeks, no general‑availability date has been confirmed, creating a significant divergence between the current crowd‑implied probability of 0% and analyst expectations that a public release may occur before the settlement window ends in July 2026[3][4].

Historical precedents from the GPT‑5.1 to GPT‑5.5 progression show that incremental updates typically follow a three‑to‑four‑week cadence, with GPT‑5.6 surfacing just three weeks after GPT‑5.5 in backend logs before a formal rollout[2]. However, markets have frequently misjudged model release dates this year, and canary signals can persist for months without triggering a public launch, meaning the 89% Polymarket probability for a June‑30 release is plausible but not load‑bearing[2]. Traders should monitor for the simultaneous release of a new system card and deployment safety hub entry, as well as version‑bump updates in Codex logs, which historically mark the first public surface for a new model[2].

Key catalysts include OpenAI’s planned expansion of API and Codex access to individual consumers, alongside the July launch of GPT‑5.6 Sol on Cerebras hardware at up to 750 tokens per second, which may accelerate broader availability[7]. Recent leaks suggest OpenAI is preparing a price war with Anthropic by drastically cutting token prices, a business play that could hasten a public debut if competition intensifies further[8]. The absence of a confirmed date, combined with regulatory delays, suggests the market’s 0% probability may understate the likelihood of a release before the settlement deadline, particularly if the US government’s early‑access request is resolved swiftly[3].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.