Where can you watch classic Doctor Who episodes on the internet for free?

* [BritBox](https://www.britbox.com) is a subscription streaming service that offers classic Doctor Who episodes.

* [The Roku Channel](https://therokuchannel.roku.com) offers a selection of classic Doctor Who episodes for free with ads.

* [Pluto TV](https://pluto.tv) offers a selection of classic Doctor Who episodes for free with ads.

* [Tubi](https://tubitv.com) offers a selection of classic Doctor Who episodes for free with ads.

* [The Internet Archive](https://archive.org/) offers a collection of classic Doctor Who episodes for free. These episodes are not curated and not official sources.