Anthropic Claude claude-sonnet-4-5-20250929 End of Life
Support dates and upgrade guidance — rebuilt from live data.
Anthropic Claude claude-sonnet-4-5-20250929 is actively supported. It reaches end of life on 30 Nov 2026.
Support timeline
Official dates from the Anthropic Claude release process.
| Milestone | Date | Status |
|---|---|---|
| Initial release | 29 Sept 2025 | 1y ago |
| Active support ended | 30 Sept 2026 | security fixes only after this |
| Deprecated support ends | 30 Nov 2026 | in 2mo |
| Latest release | — | current |
How much runway a newer branch buys
Moving to Anthropic Claude claude-sonnet-5-5 extends security support by about 302 days.
| Branch | End of life | Days left | vs claude-sonnet-4-5-20250929 |
|---|---|---|---|
| Anthropic Claude claude-sonnet-5-5 | 28 Sept 2027 | 358 | +302 days |
| Anthropic Claude claude-opus-5-5 | 22 Sept 2027 | 352 | +296 days |
| Anthropic Claude claude-mythos-5-1 | 1 Sept 2027 | 331 | +275 days |
| Anthropic Claude claude-fable-5-1 | 1 Sept 2027 | 331 | +275 days |
| Anthropic Claude claude-opus-5 | 24 Jul 2027 | 292 | +236 days |
| Anthropic Claude claude-sonnet-5 | 30 Jun 2027 | 268 | +212 days |
| Anthropic Claude claude-mythos-5 | 9 Jun 2027 | 247 | +191 days |
| Anthropic Claude claude-fable-5 | 9 Jun 2027 | 247 | +191 days |
| Anthropic Claude claude-opus-4-8 | 28 May 2027 | 235 | +179 days |
| Anthropic Claude claude-opus-4-7 | 16 Apr 2027 | 193 | +137 days |
| Anthropic Claude claude-sonnet-4-6 | 17 Feb 2027 | 135 | +79 days |
| Anthropic Claude claude-opus-4-6 | 5 Feb 2027 | 123 | +67 days |
| Anthropic Claude claude-opus-4-5-20251101 | 24 Nov 2026 | 50 | -6 days |
| Anthropic Claude claude-haiku-4-5-20251001 | 15 Oct 2026 | 10 | -46 days |
| Anthropic Claude claude-sonnet-4-5-20250929 | 30 Nov 2026 | 56 | this branch |
Frequently asked questions
When does Anthropic Claude claude-sonnet-4-5-20250929 reach end of life?
Anthropic Claude claude-sonnet-4-5-20250929 reaches end of life on 30 Nov 2026 — 56 days from now. After that date it receives no security fixes.
Is Anthropic Claude claude-sonnet-4-5-20250929 still supported?
Yes. Anthropic Claude claude-sonnet-4-5-20250929 is currently maintained. Latest release: —.
What happens when Anthropic Claude claude-sonnet-4-5-20250929 reaches end of life?
Security fixes stop. After 30 Nov 2026 this branch receives no further updates under standard support.
How long do I have to upgrade from Anthropic Claude claude-sonnet-4-5-20250929?
56 days. Moving to Anthropic Claude claude-sonnet-5-5 instead buys roughly 302 more days of security support.