IBM z/OS End of Life (EOL) Dates & Support Timeline
Complete end-of-life dates, support windows, and security status for all IBM z/OS versions. Data sourced from endoflife.date and official vendor documentation. Updated at every deploy.
| Version | Latest Release | Release Date | EOL Date | Extended Support | Days | Status |
|---|---|---|---|---|---|---|
| 2.1 | 2.1.0 | Sep 30, 2013 | Sep 30, 2018 | Jan 31, 2026 Extended support (ended) |
2857 days past EOL | EOL |
| 2.2 | 2.2.0 | Sep 30, 2015 | Sep 30, 2020 | Sep 30, 2027 Extended support |
2126 days past EOL | EOL |
| 2.3 | 2.3.0 | Sep 29, 2017 | Sep 30, 2022 | — | 1396 days past EOL | EOL |
| 2.4 | 2.4.0 | Sep 30, 2019 | Sep 30, 2024 | — | 665 days past EOL | EOL |
| 2.5 | 2.5.0 | Sep 30, 2021 | Sep 30, 2026 | — | 65 days remaining | Warning |
| 3.1 | 3.1.0 | Sep 29, 2023 | TBD | — | Supported | Active |
| 3.2 | 3.2.0 | Sep 30, 2025 | TBD | — | Supported | Active |
Live EOL badge for your README — updates automatically at every build.
[](https://endoflife.ai/zos)
IBM z/OS lifecycle status — the real story
z/OS is the operating system of the IBM mainframe — the machines still clearing a large share of the world's card payments, insurance claims, and bank ledgers — and its lifecycle runs with a regularity most vendors should envy: a release every two years (each September), five years of support minimum, then a three-year paid Service Extension. Under IBM's 'Enhanced' policy those dates are announced in formal letters, not blog posts.
The date that matters now: z/OS 2.5 reaches end of support on September 30, 2026. Its successors 3.1 (GA September 2023) and 3.2 (GA September 2025, alongside the z17 hardware) carry no announced end dates yet — the five-year minimum puts them no earlier than 2028 and 2030. Notably, 2.5's withdrawal from marketing already happened in January 2024: you cannot buy your way back onto it.
Mainframe estates rarely miss these dates by accident — they miss them because a z/OS upgrade drags an ecosystem (CICS, Db2, IMS, COBOL compilers, ISV tools) through recertification. That is why IBM's paid extensions exist and why third-party mainframe support is a thriving market: for shops mid-migration, the bridge is often not optional. Versions 2.1 and 2.2 illustrate the pattern — their paid extensions ran or run seven-plus years past general availability.
What does IBM z/OS end of life mean for your organization?
When a version of IBM z/OS reaches end of life, the maintainers stop issuing security patches. Vulnerabilities discovered after this date are publicly disclosed on the National Vulnerability Database, exploit code appears on GitHub, and your systems remain permanently exposed.
The CVE blind spot: Most vulnerability scanners check for known CVEs but do not flag the accumulation of unpatched vulnerabilities in EOL software. With a zero-day, nobody knows about the vulnerability. With EOL software, the vulnerability is public — listed, rated, and often weaponized — but no patch will ever exist. This is the most dangerous gap in enterprise security posture.
Organizations running EOL IBM z/OS should treat it as a vulnerability class in their risk register, apply compensating controls (network segmentation, enhanced monitoring, access restriction), and prioritize migration to a supported version.
Extended Support Options
If you cannot migrate immediately, extended support vendors provide continued security patches for EOL IBM z/OS versions. This is a bridge, not a permanent solution — plan your migration in parallel.
IBM z/OS has 4 versions past end of life — security patches have stopped, but CVE disclosures haven't. The good news: extended support for IBM z/OS exists — vetted vendors ship security patches for years past the official date. Tell us where to reach you and we'll reply with matched options and pricing guidance.