Umbraco 13 LTS End of Life: December 14, 2026
Umbraco 13 reaches end of life on December 14, 2026. The date is on Umbraco's own Long-term Support (LTS) and End-of-Life (EOL) page, which lists Umbraco 13 as an LTS release with a release date of December 14, 2023, a Security phase beginning December 14, 2025, and end of life on December 14, 2026. Umbraco's policy gives an LTS major three years: six months in the Active phase, eighteen in the Support phase, twelve in the Security phase. Umbraco 13 is in the last of the three. For the rest of 2026 it gets security fixes and nothing else; from the end-of-life date it gets nothing, and the move is to Umbraco 17, the LTS release that followed it.
Umbraco's three phases, in Umbraco's words
Umbraco ships two kinds of major release, Standard-term Support (STS) and Long-term Support (LTS), and every major passes through the same three phases. Paraphrasing the LTS and EOL page, read on October 11, 2026, with Umbraco's own key phrases quoted:
Active phase. The first six months of a major. Minor releases ship about every six weeks with "minor features and bug fixes - no breaking changes".
Support phase. Umbraco fixes "bugs, regressions, and security issues" and allows new Umbraco Cloud projects on the version. It lasts three months for an STS major and eighteen for an LTS major.
Security phase. In Umbraco's words, "only security issues are fixed". It lasts three months for STS and twelve for LTS; after it "the release is End of Life, and it is no longer recommended".
So an STS major lives one year (6 + 3 + 3 months) and an LTS major three (6 + 18 + 12). The page also explains why the LTS releases land when they do: a new Umbraco LTS major follows shortly after each new .NET LTS, and it names Umbraco 17 as the most recent LTS, "supporting .NET 10 LTS". Umbraco 13 was the LTS built on .NET 8, which is why its clock and .NET 8's run out within weeks of each other (below).
Where each current version stands
The four versions Umbraco's schedule lists as active or recently ended, with the dates from that page as we serve them on the Umbraco lifecycle page. "Security phase from" is the day the Support phase ends and security-only fixes begin; "End of life" is the day fixes stop. Each version links to its live status page.
| Version | Type | Released | Security phase from | End of life | Status |
|---|---|---|---|---|---|
| Umbraco 18 | STS | June 25, 2026 | March 25, 2027 | June 25, 2027 | Approaching |
| Umbraco 17 | LTS | November 27, 2025 | November 27, 2027 | November 27, 2028 | Supported |
| Umbraco 16 | STS | June 12, 2025 | March 12, 2026 | June 12, 2026 | EOL |
| Umbraco 13 | LTS | December 14, 2023 | December 14, 2025 | December 14, 2026 | Approaching |
Umbraco 14 and 15, the two STS releases between 13 and 16, are already past end of life, as is Umbraco 10, the LTS before 13, which ended on June 16, 2025. Umbraco's schedule also lists three upcoming releases: Umbraco 19 (STS) planned for December 2026, Umbraco 20 (STS) for June 2027 and Umbraco 21, the next LTS, for December 2027. Those are plans and can move; they are not in the table. Every Umbraco version back to 6 is on our Umbraco lifecycle page.
Key dates
- December 14, 2023: Umbraco 13 LTS released.
- November 27, 2025: Umbraco 17 LTS released, the long-term support release that follows 13.
- December 14, 2025: Umbraco 13 moved from the Support phase to the Security phase.
- June 12, 2026: Umbraco 16 (STS) end of life.
- November 10, 2026: .NET 8, the framework Umbraco 13 is built on, reaches end of support.
- December 14, 2026: Umbraco 13 end of life. This page.
- November 27, 2027: Umbraco 17 moves to its Security phase.
What the Security phase means for a 13 site
Since December 14, 2025 an Umbraco 13 site has been getting one kind of release: patches for security issues. Umbraco's phase text draws the line itself. The Support phase "fixes bugs, regressions, and security issues"; the Security phase fixes security issues only. A rendering bug, a regression in the backoffice or a broken package compatibility in 13 is fixed in a supported version, not in 13. The schedule shows the line is live: the most recent 13 release is dated September 14, 2026, inside the Security phase.
Two more consequences follow from Umbraco's own text. First, Umbraco Cloud: the page says "Versions in Security or EOL phases can't be used for new projects or baselines", so a 13 site can keep running on Cloud but cannot be cloned into a new project there. Second, the add-ons: "The add-ons follow the same LTS timeline as the CMS", so Umbraco Forms, Commerce, Workflow, Engage, UI Builder and Deploy 13 share the December 14, 2026 date.
After December 14, 2026 the security fixes stop too. Umbraco's page does offer a paid route past that date, "Extended Long-term Support (XLTS)" for LTS versions, described as a way to "Keep your Umbraco projects secure and compliant past the End-of-Life date". Whether that or a third-party arrangement fits a given estate is the question the form above exists to answer.
How to check what you are running
In the Umbraco backoffice, the version is shown in Settings under Help, or on the login screen's footer in recent versions. From the project, open the .csproj file and read the Umbraco.Cms package reference:
<PackageReference Include="Umbraco.Cms" Version="13.x.y" />A version starting 13. means the site is on the line that ends December 14, 2026. The same file's TargetFramework line (net8.0 for Umbraco 13) tells you which .NET clock applies. For many sites at once, an SBOM records NuGet packages as pkg:nuget purls; our SBOM end-of-life audit guide shows how to read them, and the EOL Checker and API resolve the result against the dates above.
Upgrade path: 13 to 17
- Pick the LTS, not the newest number. Umbraco 18 is newer than 17 but is an STS release: its Security phase begins March 25, 2027 and it ends on June 25, 2027. Umbraco 17 LTS runs to November 27, 2028. For a site that moved to 13 because it was an LTS, 17 is the like-for-like destination.
- Expect a major upgrade, not a minor one. Four majors sit between 13 and 17, and Umbraco rewrote the backoffice in the versions after 13. Umbraco's documentation at docs.umbraco.com carries version-specific upgrade notes for each major; read the ones for 14 through 17 before estimating, because custom backoffice extensions, property editors and packages written for 13 are the part most likely to need work.
- Move the framework in the same pass. Umbraco 17 requires .NET 10. Update the
TargetFramework, the hosting environment and any build pipeline images together with the Umbraco packages. - Check every add-on and package. Umbraco's add-ons share the CMS version number; third-party packages have their own 17-compatible releases or do not. Inventory them first.
- Plan the next step now. Umbraco 17 moves to its Security phase on November 27, 2027; Umbraco's schedule plans Umbraco 21, the next LTS, for December 2027. Moving LTS to LTS every two years keeps a site out of the Security phase almost entirely.
Frequently Asked Questions
When does Umbraco 13 reach end of life?
Umbraco 13 LTS reaches end of life on December 14, 2026. That is the end-of-life date on Umbraco's Long-term Support and End-of-Life schedule, three years after the version's release on December 14, 2023. Umbraco's policy says that after the Security phase the release is End of Life and it is no longer recommended.
Is Umbraco 13 still supported?
Partly, until December 14, 2026. Since December 14, 2025 Umbraco 13 has been in Umbraco's Security phase, in which, in Umbraco's words, only security issues are fixed. Bugs and regressions are no longer fixed in 13, and new Umbraco Cloud projects cannot be created on it. After the end-of-life date no fixes of any kind are released for 13.
Which version should an Umbraco 13 site move to?
Umbraco 17 LTS, released on November 27, 2025, which Umbraco's schedule carries to a Security phase starting November 27, 2027 and end of life on November 27, 2028. It is the long-term support release that follows 13; Umbraco 14, 15, 16 and 18 are standard-term releases with a one-year life each. Umbraco 17 is built on .NET 10, so the move also replaces the .NET 8 runtime under a 13 site.
Does .NET 8 ending affect Umbraco 13?
Yes. Umbraco's own documentation says Umbraco 13 is based on .NET 8, and .NET 8 reaches end of support on November 10, 2026, five weeks before Umbraco 13 does. From that date the framework under an Umbraco 13 site stops receiving Microsoft's security updates even while Umbraco's Security phase for 13 is still running.
Related
- Umbraco 13 — the live status page with its EOL Risk Score
- Umbraco — every version's dates
- Umbraco 17 · Umbraco 18 · Umbraco 16 — the neighbouring versions
- .NET 8 · .NET end of life in 2026 — the runtime under every Umbraco 13 site
- SBOM end-of-life audit — finding NuGet packages in an SBOM
- 2026 EOL calendar — every dated end of support this year
- Umbraco Long-term Support and End-of-Life — the vendor page the phases and dates were read from
- How we verify our dates — the rules every number on this site is held to