# U.K. Annual Inflation 2026 The annual inflation question for the U.K. uses the twelve months ending in December. It does not average the monthly inflation rates observed throughout the year, so the final months can change the answer substantially. Canonical article: https://www.homeincomelab.com/stories/uk-annual-inflation-in-2026 Publisher: The Outlook By: The Outlook editorial desk Category: Economy Analysis as of: 2026-10-04T09:57:48.323Z Decision guide market prices observed: 2026-10-04T09:57:48.323Z Published: 2026-10-04T09:57:48.323Z ## Quick answer The annual inflation question for the U.K. uses the twelve months ending in December. The leading open contract, “3.5–3.9%”, was priced at 56.65% for Yes in the October 4 snapshot. Use the official December 2026 twelve-month CPI change at one decimal precision. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ## Key takeaways - Use the official December 2026 twelve-month CPI change at one decimal precision. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) - The annual inflation question for the U.K. uses the twelve months ending in December. - The contract expects the release in January 20, 2027. If missing by the next month’s scheduled release date, use the last available month. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ## The question behind the headline The annual inflation question for the U.K. uses the twelve months ending in December. It does not average the monthly inflation rates observed throughout the year, so the final months can change the answer substantially. At the October 4, 2026 market snapshot, 3.5–3.9% carried a 56.65% Yes price. Other open contracts included 3.0–3.4% at 26.5%; 4.0-4.4% at 7.55%. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ## The condition that changes the answer Use the official December 2026 twelve-month CPI change at one decimal precision. Use the index and annual comparison identified in the named statistical release. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) The contract expects the release in January 20, 2027. If missing by the next month’s scheduled release date, use the last available month. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ## Evidence for and against the leading outcome The leading bracket needs the final published annual change to land inside its boundaries, not just move in the same direction. Base effects and new monthly price movements can shift the December comparison across a boundary while the broad inflation narrative stays similar. The next useful checks are december-over-December comparison; the exact index and rounding precision; release calendar and missing-data fallback. The linked primary references make the process and named data source inspectable. [2](https://www.ons.gov.uk/economy/inflationandpriceindices/bulletins/consumerpriceinflation/previousreleases)[3](https://www.ons.gov.uk/releasecalendar) ## A closer look at the market The leading listed option was 30.15 percentage points above the next quoted option. That difference measures market pricing, not a vote margin or a measured lead in real-world evidence. A price above 50% still leaves room for another outcome; it is not a guarantee or an independently validated forecast. The event had approximately $133,087 in total traded volume at observation. That is a record of turnover across this event, not a count of distinct people, a search-volume estimate or proof that every child contract is easy to trade. The analytical quote is fixed to the timestamp shown here; later live prices can differ. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) The useful conclusion is conditional: the leading option needs to satisfy the whole outcome definition, not just one favorable part of the story. ## A fact worth knowing CPI is the specified measure here; other inflation indexes do not substitute for it. Source: [Polymarket — event, child contracts and resolution rules](https://polymarket.com/event/uk-annual-inflation-in-2026) ## Weighing the outcome ### Outcome in focus 3.5–3.9% ### Supporting case The leading bracket needs the final published annual change to land inside its boundaries, not just move in the same direction. ### Challenging case Base effects and new monthly price movements can shift the December comparison across a boundary while the broad inflation narrative stays similar. ### What to watch - December-over-December comparison - The exact index and rounding precision - Release calendar and missing-data fallback ### What may already be priced in The analysis starts from 56.65% for the Yes side of “3.5–3.9%”. A view merely agreeing that this is plausible does not show that the price understates it. The probability, rule and remaining time all have to be compared. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ### Assessment The useful conclusion is conditional: the leading option needs to satisfy the whole outcome definition, not just one favorable part of the story. ## How the market resolves Use the official December 2026 twelve-month CPI change at one decimal precision. Use the index and annual comparison identified in the named statistical release. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ## Timing and deadline The contract expects the release in January 20, 2027. If missing by the next month’s scheduled release date, use the last available month. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ## Questions and answers ### What exactly would settle this market? Use the official December 2026 twelve-month CPI change at one decimal precision. Use the index and annual comparison identified in the named statistical release. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ### What is the deadline, and can settlement come later? The contract expects the release in January 20, 2027. If missing by the next month’s scheduled release date, use the last available month. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ### Does the quoted probability show an advantage? No. 56.65% is the observed Yes price for “3.5–3.9%”, not a verified probability from independent research. A useful assessment needs evidence that changes the expected chance under the exact rules, plus the actual price available at the time. [1](https://polymarket.com/event/uk-annual-inflation-in-2026) ## Related market contracts - [3.5–3.9%](https://polymarket.com/event/uk-annual-inflation-in-2026/will-the-uks-2026-inflation-be-between-3pt5-and-3pt9) - [3.0–3.4%](https://polymarket.com/event/uk-annual-inflation-in-2026/will-the-uks-2026-inflation-be-between-3pt0-and-3pt4) - [4.0-4.4%](https://polymarket.com/event/uk-annual-inflation-in-2026/will-the-uks-2026-inflation-be-between-4pt0-and-4pt4) ## Market source [View the event on Polymarket](https://polymarket.com/event/uk-annual-inflation-in-2026) For timestamped market prices, see the canonical HTML article. Prices can change independently of this analysis. ## Sources and further reading 1. [Polymarket — event, child contracts and resolution rules](https://polymarket.com/event/uk-annual-inflation-in-2026) 2. [ons.gov.uk — official source](https://www.ons.gov.uk/economy/inflationandpriceindices/bulletins/consumerpriceinflation/previousreleases) 3. [ons.gov.uk — official source](https://www.ons.gov.uk/releasecalendar) This is AI-assisted, source-linked explanatory journalism. We distinguish facts from interpretation and revise material errors. [How we work](https://www.homeincomelab.com/methodology) · [Corrections and contact](https://www.homeincomelab.com/contact)