Originally published on endoflife.ai.
Ember.js moves on a steady release train, designating Long-Term Support (LTS) releases on a regular cadence — which means older versions reach end of life just as steadily. As of now, Ember 6.x is the current line, with 6.8 and later supported; Ember 6.4 reached EOL on June 21, 2026, and every 5.x release and earlier is end of life, including the once-ubiquitous 3.28 LTS.
Ember version EOL schedule
| Version | End of Life | Status | Risk Score |
|---|---|---|---|
| Ember ≤ 4.x | 2023 – 2024 | EOL | 60 |
| Ember 5.4 (LTS) | Dec 22, 2024 | EOL | 55 |
| Ember 5.8 (LTS) | Jun 15, 2025 | EOL | 50 |
| Ember 5.12 (LTS) | Oct 12, 2025 | EOL | 50 |
| Ember 6.4 (LTS) | Jun 21, 2026 | Just EOL | 35 |
| Ember 6.8 (LTS) | Dec 7, 2026 | Supported | 20 |
| Ember 6.11+ (latest) | Active | Current | 20 |
How Ember's LTS cadence works
Ember releases on a roughly six-week train and periodically blesses a release as LTS. The LTS releases are what most teams target — they get a longer, fixed support window than the six-week releases. When that window ends, the LTS (and everything before it) is EOL.
A new LTS arrives roughly every couple of quarters, and an older one drops off at a similar rhythm. Like Angular, Ember rewards a standing upgrade habit: stay on the current or immediately-previous LTS and upgrades are small; let several windows pass and the gap compounds.
Target the LTS, not the bleeding edge. Pin to the most recent LTS (or the one just behind it with an upgrade scheduled), put its EOL date in your roadmap, and move before it lands.
The Octane shift — why 3.x apps got stuck
The reason so many Ember apps are stranded years back isn't the cadence — it's Octane. Ember Octane (default in the 3.x series) modernised Ember substantially: Glimmer components, tracked properties, native classes, and a move away from the classic object model. A genuine improvement, but it changed enough idioms that migrating a large classic-Ember app is real work.
Many teams paused on a late classic 3.x release — 3.28 being the common resting point — and never jumped. Those apps are now multiple majors and several years past EOL (3.28 has been EOL since January 2023).
Ember 6.x — the supported line
Ember 6.8 LTS (supported through December 2026) is the conservative target; the latest release (6.11+) carries the newest features and longest runway. Both score 20 (Low). Modern Ember is Octane-by-default and considerably leaner than the 3.x-era apps people remember.
Upgrading with ember-cli-update
-
Find your version and LTS gap.
ember --version+package.json, cross-referenced against the table. - Run ember-cli-update, one LTS at a time. It migrates files/config toward a target and surfaces diffs to resolve. Step LTS to LTS rather than jumping the whole gap.
- Clear deprecations before each major. Ember's deprecation warnings are your migration checklist.
- Adopt Octane idioms where you're still classic. Glimmer components, tracked properties, native classes — codemods handle much of it.
- Update addons in lockstep. A lagging addon is the most common blocker; replace any that are abandoned.
Stranded on classic Ember?
Apps pinned to 3.28 or earlier sometimes need a real, scheduled project to reach a supported 6.x — the Octane jump plus the version gap is genuine work. Extended support can keep an EOL Ember app patched in the interim.
Full guide, live per-LTS Risk Scores, and the rest of the framework lifecycle data at endoflife.ai. Check your whole stack free with the Stack Scanner.