Gemini 3.9 Flash Release Date: What Google's Own Pages Show

As of 16 October 2026, Google has not announced a Gemini 3.9 Flash or a Gemini 4 Flash, and none of its pages we checked gives a date for either; its newest general-purpose Flash model is Gemini 3.8 Flash, released on 2 September 2026. On versus, the prediction Will Google release Gemini Flash version 3.9 or later by 31 Oct? showed Yes at 39.5p and No at 60.5p at 07:30 UK time on 16 October 2026.

A price of 39.5p on Yes is the market's estimate of a 39.5% chance that a qualifying Flash model goes public before the cut-off. It is a reading, not a statement from Google. This guide is for readers in Great Britain.

Google's Flash releases since Gemini 3, with dates

Dates are from Google's Gemini API release notes, opened at 06:27 BST on 16 October 2026, for general-purpose Flash models, with two later entries added for context:

• 17 December 2025: Gemini 3 Flash, launched as a preview. The models page still lists it under Preview.
• 19 May 2026: Gemini 3.5 Flash, released as generally available (GA), Google's label for a stable production model.
• 21 July 2026: Gemini 3.6 Flash, GA, introduced in a blog post with 3.5 Flash-Lite and 3.5 Flash Cyber.
• 13 August 2026: Gemini 3.7 Flash, GA, which its launch post says came three weeks after 3.6 Flash.
• 2 September 2026: Gemini 3.8 Flash, GA. Google's post that day called it the third Flash release in six weeks and introduced 3.8 Flash Cyber for trusted defenders in its Fairwind Program; Google Cloud lists that model as GA behind an allowlist from 16 September.
• 8 October 2026: 3.7 Flash and 3.5 Flash were deprecated, with requests routed to 3.8 Flash and 3.6 Flash.
• 13 October 2026: Gemini 4 Argon, which Google announced on 30 September for trusted cyber defenders first, reached GA through the Gemini API. It is a frontier model, not a Flash.

The gaps between those five Flash launches were 153, 63, 23 and 20 days. By 16 October, 44 days had passed since 3.8 Flash, and 31 October is day 59. That is arithmetic on past dates, not a schedule; Google has published no timetable.

Does Google mention a 3.9 Flash anywhere?

No. These Google pages, searched on the morning of 16 October 2026 (times in BST), mention neither a Gemini 3.9 Flash nor a Gemini 4 Flash:

• Gemini API release notes, 06:27: the newest entry is dated 13 October 2026 and covers Gemini 4 Argon.
• Gemini API models page, 06:27: Gemini 4 Argon is the only Gemini 4 model, and the Gemini 3 list opens with 3.8 Flash, "Our most intelligent Flash model".
• Deprecations table, 06:29: 3.8 Flash, released 2 September 2026, has "No shutdown date announced".
• Google's blog, Gemini models section, 06:29: the newest posts, dated 13 October 2026, are all about Gemini 4 Argon.
• Google DeepMind's Flash page, 06:31: titled Gemini 3.8 Flash.
• Gemini Enterprise Agent Platform release notes, 06:32: these replace Google's old Vertex AI notes, and the newest entry, dated 14 October 2026, names no new Gemini Flash.

The closest Google comes is the last line of its post on Gemini 4 Argon of 13 October 2026, which looks forward to "bringing you the rest of the Gemini 4 family" without naming a model or a date. Our Gemini 4 release date guide covers Argon itself.

What the prediction counts

Every market on versus names the source that settles it before you trade. Here Google's official information leads, backed by matching reports from reliable news outlets. The rules set five tests:

• The name. Gemini and Flash must both be in the name or model code, with a number of 3.9 or higher. Capitals, extra words or a date in the name do not matter. A whole-number jump counts, so a Gemini 4 Flash would qualify; Gemini 4 Argon does not, because Flash is not part of its name.
• The type. Only a general-purpose Flash. Flash-Lite is out, and so are the image, Omni video, Cyber, text-to-speech and Live voice models.
• Nothing older. Anything numbered below 3.9 fails, including new snapshots or a wider rollout of 3.8 Flash, which came out one day before the window opened.
• Open to anyone. A public beta or an open rolling waitlist is enough; invitation-only access or a closed test is not. A preview any developer can use looks like a public beta; one kept to chosen testers does not. Full general availability is not needed, though the rules decide each case.
• Proof. Google says publicly that general access is open, or actually offers the model on its official website under a clear name. Placeholders, labelling errors and models nobody can reach do not count.

The window runs from 00:00 UTC on 3 September 2026 (01:00 BST) to 11:59 pm Eastern Time on Saturday 31 October. New York stays on daylight time until 1 November, so that is 03:59 UK time on Sunday 1 November, after UK clocks go back to GMT on 25 October. The prediction also lists an end date of 23:59 UTC on 31 October, which is 23:59 UK time that night, so check both before you trade. With no qualifying public model in time, the prediction settles No.

What to watch before the cut-off

• Any day: 3.6, 3.7 and 3.8 Flash each appeared on launch day in the Gemini API release notes, on Google's blog and in Google Cloud's release notes, with a model page of its own. Entries like those for a public, general-purpose Flash numbered 3.9 or above would meet the naming test.
• 23 October 2026: the only future date in the Gemini API release notes before the cut-off, when an older Deep Research agent shuts down. That is not a Flash event.
• 31 October and 1 November 2026: the listed end date and the cut-off in the rules. A qualifying release before then would settle Yes at 100p and No at 0p; without one, No settles at 100p and Yes at 0p.
• 17 November 2026: the deprecations table's earliest possible shutdown date for two Gemini 3.1 previews, Flash TTS and Flash Live. It falls after the cut-off, and neither type counts. 3.8 Flash has no shutdown date.

Before you trade

A price runs from 0p to 100p and is the market's estimate of a chance. A winning contract settles at 100p and a losing one at 0p, so you can lose the whole amount you put into a position. versus adds a 2% transaction fee on top of the stake and shows it before you confirm, and while a market is open you can sell your position at the current price.

versus is licensed by the UK Gambling Commission under account 101143, which you can check on the Commission's public register. Positions settle in ordinary money, not cryptocurrency, and customer money is held separately from company money. Safer Play tools, including deposit limits, loss limits, reality checks, time out and self exclusion, sit alongside GAMSTOP.

Frequently asked questions

Is Gemini 3.9 Flash out yet?

No. As of 16 October 2026, the newest general-purpose Flash on Google's pages is Gemini 3.8 Flash, released on 2 September 2026, and none of the pages we checked mentions a 3.9. Google's names put the number first, so Gemini Flash 3.9 and Gemini 3.9 Flash mean the same.

When is the Gemini 3.9 Flash release date?

Google has not given one. The versus prediction asks whether a qualifying Flash numbered 3.9 or higher goes public by 11:59 pm Eastern Time on 31 October 2026, which is 03:59 UK time on 1 November.

Would a Gemini 4 Flash count?

Yes, if it is a general-purpose Flash that the public can use before the cut-off. Gemini 4 Argon does not, as its name has no Flash.

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