AI policy
OpenAI previews GPT-5.6 Sol, Terra and Luna, but locks the launch
The brief: OpenAI's new flagship trio is real, priced and gated to about 20 government-approved partners.
The answer
OpenAI previewed GPT-5.6 (Sol, Terra, Luna) on 26 June 2026 to ~20 government-approved partners only.
What happened
On 26 June 2026 OpenAI previewed GPT-5.6 as three durable tiers. Sol is the top flagship for the hardest reasoning, coding, agentic and security work. Terra is the balanced everyday model, pitched at roughly GPT-5.5-level performance for about half the cost. Luna is the budget tier. Under the new naming, the number marks the generation and the names mark capability tiers that advance on their own cadence. An "ultra" mode splits work across multiple sub-agents, and Sol is due on Cerebras at up to 750 tokens/sec in July.
The catch
At the US government's request, OpenAI started with a limited preview to about 20 trusted partners approved by the government, reached via the OpenAI API and Codex — not in ChatGPT. It follows a Trump executive order of 2 June 2026 directing agencies to benchmark new models and designate "covered frontier models" before wide release. OpenAI says it treats Sol, Terra and Luna as High capability in cybersecurity and biological/chemical under its Preparedness Framework, and that none reach High in AI self-improvement. It also says the gate should not become the long-term default, and expects to expand access in the coming weeks. This is the same federal machinery that paused Anthropic's Fable 5 and Mythos 5 in June — the access gate is now a pattern across labs, not a single-lab measure.
The money
Pricing per 1M tokens, input/output:
| Tier | Role | Price in/out |
|---|---|---|
| Sol | Top flagship | $5 / $30 |
| Terra | Balanced everyday | $2.50 / $15 |
| Luna | Budget | $1 / $6 |
OpenAI says it "does not believe this kind of government access process should become the long-term default," arguing it keeps the best tools from users, developers, enterprises and cyber defenders who need them.
The GPT-5.6 family is accessible only to a limited set of preview partners for now, at the US government's request, before wider availability.
Frequently asked questions
What is GPT-5.6 Sol, Terra and Luna?
Why can't I use GPT-5.6 yet?
How much does GPT-5.6 cost?
Why did the government gate the launch?
Sources
- Previewing GPT-5.6 Sol: a next-generation model — OpenAI, 26 June 2026
- OpenAI unveils GPT-5.6 Sol, Terra and Luna models — but only accessible to limited preview partners for now, per US Gov — VentureBeat, 26 June 2026
- OpenAI releases powerful new GPT-5.6 model under restrictions — Axios, 26 June 2026