Anti-pattern series: Not unsubscribing from Observables
This article explains how Angular 16 improves observable cleanup using takeUntilDestroyed and recommends applying it in services rather than components, so all subscribers are automatically protected from memory leaks.
Alain Chautard
January 15, 2026
We covered this in our newsletter before: Observables can cause memory leaks if we don’t unsubscribe from them.
Before Angular 16, there were a few different techniques available to unsubscribe automatically, the best of those being the async pipe (and yes, it’s possible to use the async pipe 100% of the time if you use the tricks highlighted here – no excuses).
With Angular 16, things are even better, as you can use the new takeUntilDestroyed operator as follows:
But here’s my million-dollar tip for today: Instead of using takeUntilDestroyed in your components, use it in the services that expose such Observables:
That way, whether you use an async pipe or not, your components are covered. That’s one of the nice things about Observables: We can change them whenever and wherever we want using pipe(), including in our services – so that all subscribers benefit from that change downstream.
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