An AngularJS to Angular migration is a rewrite of your front end in slow motion, and the honest plan is to treat it that way. AngularJS support ended on December 31, 2021, so any AngularJS app still in production has gone almost five years without official fixes. The good news is that you can migrate one screen at a time while the app keeps shipping. The bad news is that the "one screen at a time" part takes longer than anyone budgets.
I have seen teams stall at 40% migrated for a year. The plan below is built to avoid that.
Key Takeaways
- AngularJS support ended December 31, 2021 (the original July 2021 date was pushed back six months).
- Angular changed its policy: from v22, each major gets 24 months of support (12 active, 12 LTS), with one major a year. v22 is current and supported to June 2028.
- The hybrid approach with ngUpgrade lets both frameworks run side by side so you migrate incrementally. It works, but every week in hybrid mode costs you build complexity and bundle size.
- Time-box the hybrid phase. Migrate the shared services first, then the most-changed screens, and set a hard date to delete AngularJS.
The Dates You Are Planning Against
The official AngularJS docs state that "AngularJS support has officially ended as of January 2022." Long-term support had been scheduled to end in July 2021 and was extended six months, to December 31, 2021.
On the Angular side, the release policy changed with v22. Until v22, Angular shipped a major every six months with 18 months of support. Now:
| Angular version | Status (Oct 2026) | Released | Support ends |
|---|---|---|---|
| v22 | Active | 2026-06-03 | June 2028 |
| v21 | LTS | 2025-11-19 | June 2027 |
| v20 | LTS | 2025-05-28 | 2026-11-28 |
| v2 to v19 | Unsupported | n/a | Already ended |
Target v22. Starting a migration on v20 means landing on a version that loses support in eight weeks. The yearly cadence from v22 on also makes Angular easier to keep current once you are there, which matters if the reason you are in this mess is that nobody upgraded for six years.
AngularJS to Angular Migration: Hybrid or Big Bang
The release page points to the official Upgrading from AngularJS guide, which now lives on the archived v17 docs site. Its core idea: run AngularJS and Angular in the same app with the `@angular/upgrade/static` package, downgrade new Angular components so AngularJS templates can use them, and upgrade AngularJS services so Angular code can call them. You move pieces across until nothing AngularJS is left.
The big-bang alternative is rebuilding the whole front end in Angular (or React, or Vue) while the old app runs, then switching over. For anything over about 30 screens, I recommend hybrid. Big-bang rewrites have a well-earned reputation: the new app chases a moving target, and most big rewrites fail for exactly that reason.
What makes hybrid succeed:
1. Prepare the AngularJS code first. Move to component-style directives, one component per file, and TypeScript if you can. This makes each later step mechanical.
2. Migrate services before screens. Auth, API clients and state are shared by everything. Once they live in Angular, each screen migration gets cheaper.
3. Pick screens by change frequency. Migrate the screens your team edits every sprint first. The settings page nobody touches can wait until the end.
4. Set a kill date. Hybrid mode doubles the frameworks in your bundle and your test setup. Pick the date AngularJS gets deleted and protect it.
What Breaks
The places teams lose time are predictable: `$scope` and two-way binding patterns that have no direct equivalent, `$rootScope` events used as a global message bus, third-party AngularJS directives (date pickers, grids, upload widgets) with no Angular version, and routing, since you can only have one router in charge of the URL at a time. The test suite usually needs rewriting too, because AngularJS-era Karma and Protractor setups do not carry over cleanly.
A Concrete Version
A hypothetical B2B admin app: AngularJS 1.8, 85 screens, 140 directives, 45 services, 30,000 lines of JavaScript, a jQuery date picker and a commercial grid component, plus 400 unit tests.
Estimate:
- Prep work (component-style refactor, TypeScript setup, build tooling for hybrid): 120 hours.
- 45 services moved to Angular at about 4 hours each: 180 hours.
- 85 screens at an average of 10 hours each including their directives: 850 hours.
- Replacing the date picker and grid with Angular-native components: 80 hours.
- Router cutover and removing AngularJS: 60 hours.
- Test rewrite (400 tests, about 15 minutes each): 100 hours.
- QA and staged rollout: 90 hours.
Total: 120 + 180 + 850 + 80 + 60 + 100 + 90 = 1,480 hours. Three senior front-end engineers at about 35 productive hours a week each produce 105 hours a week, so roughly 14 weeks, a bit over three months, if they work on nothing else. With one engineer half-time, it runs past a year and a half, which is how teams end up stuck at 40%.
The Honest Counterpoint
Angular is the natural target because the migration tooling exists. It is not the only reasonable one. If your team now writes React everywhere else, or you cannot hire Angular engineers fast enough, rebuilding the AngularJS app in React screen by screen behind a reverse proxy is a valid path. You lose ngUpgrade's in-page interop, but you gain one front-end stack for the whole company. I lay out that trade-off in React vs Vue and the broader rewrite or refactor question.
And if the app has five users and changes twice a year, isolate it behind an internal network, keep it running, and spend the 1,480 hours somewhere that makes money.
Who Does the Work
This is a perfect job for a small dedicated team with a finish date, separate from the people shipping features. One internal engineer who knows the business rules acts as reviewer; two or three senior front-end engineers do the migration. Hire for people who have shipped a hybrid migration before, and test them on it. The Angular developer hiring guide has the interview questions.
Ruzora sends a vetted shortlist of senior front-end engineers within 72 hours. See front-end engineers or request a shortlist with Angular in the brief.
Frequently Asked Questions
Is AngularJS to Angular migration worth it in 2026?
For an app that is actively developed, yes. AngularJS has had no official support since December 31, 2021, and every new hire has to learn a framework that is dead. For a rarely-changed internal tool, isolating it can be the cheaper choice.
How long does an AngularJS to Angular migration take?
For a mid-size app of 50 to 100 screens, three to six months with a dedicated team of two or three senior engineers. Part-time efforts routinely take years.
Can AngularJS and Angular run in the same app?
Yes. The official upgrade approach uses `@angular/upgrade/static` to run both side by side and migrate incrementally. Keep the hybrid period short, because it adds bundle size and build complexity.
The Bottom Line
The AngularJS to Angular migration is overdue for anyone still on AngularJS. Target Angular v22, go hybrid with a kill date, and staff it with a team whose only job is finishing. If you need that team, talk to us.
Roberto Espinoza is CEO of Ruzora, which helps US startups hire pre-vetted senior LATAM engineers, with a vetted shortlist in 72 hours. See available engineers.
