Assign GitHub issue to multiple people

Here is the info on Multiple assignees on Issues and Pull requests

I couldn't find any update on the topic, but it seems that Github changed the assignees' policy and now in the public projects you can assign up to 10 people:

But on the private projects you are limited back to a single person:

So basically, you need to do the already mentioned approach (with @ in the issue text)

You could assign the issue to one of them and @-mention the GitHub usernames of the others, which will subscribe them to updates for that issue. If you have groups of people who will often be assigned together, you could also create teams within an organization to mention them all at once.

UPDATE: GitHub just shipped multiple assignees, so, now you can!

Use labels. Create a label for each member of your team and use these to assign team members to tasks. This is not functionally as intended but it works well!

You can add scope: person:A, person:B, etc to search and read it more easily