[git] How do I set up a private Git repository on GitHub? Is it even possible?

I intend to share my source code on an invite-only basis to a few dozen users maybe. The source code itself should not be public. Participants are allowed and encouraged to submit their changes. So I need source control, preferably Git, hosted on a public server with private access for multiple users.

I learned that it is possible to set up private Git repositories on GitHub which use https:// links. On GitHub itself such a project does not show up in searches. For participating users the project shows a "lock" icon. So there are obviously private repositories; I just don't know how set one up. A lot of tutorials use SSH to set up private repositories but they all require you to have "your own server".

I don't care about secure connections when pushing/pulling source code nor do I have trust issues with GitHub. All I care about is giving access only to users I invite. Maybe I'm naive and such a solution is only available via commercial hosting (e.g., Unfuddle, Assembla), but if not, I'd really like to know how it's done!

GitHub is a great tool in-all for making repositories. However, it does not do good with private repositories.

You're forced to pay for private repositories unless you get some sort of plan. I have a couple of projects so far, and if GitHub doesn't do what I want I just go to Bitbucket. It's a bit harder to work with than GitHub, however it's unlimited free repositories.

Once you have a paid account on GitHub, it is not obvious how to create a private repository. To create a private repository for an organization with paid account, go to https://github.com/organizations/MYORGANIZATIONNAME.

The only way I've figured how to navigate there is:

• Go to to your organization's home page: https://github.com/MYORGANIZATIONNAME
• Click on the "Edit MYORGANIZATION's Profile" button at the top right
• Click on the "GitHub" icon at the top left (non-obvious)
• Click on the "News Feed" tab (non-obvious)
• Click on the "New Repository" button at the right ...

Bitbucket - Their plans seem to be the best. They give you way more than GitHub do for free accounts - in fact, I'm still only using the free plan - no need to sign up to the paid ones; plus the interface is almost identical to GitHub.

A repository on Bitbucket can have up to five private users with unlimited public or private repositories - the only thing you seem to be paying for with the paid accounts are more users to access your private repositories.

Update (2019, latest)

Since Jan 2019, GitHub allows private repositories for up to three collaborators.

Previous answer:

Here is the comparison for free plans listed by tree main Git Cloud based solutions:

Here is the comparison for paid plans listed by tree main Git Cloud based solutions:

Conclusion:

I'm not seeing people mentioning GitLab here, but it seems like the best free private plan for me. I myself am using it with no problems.

GitHub: If you have a student account or want to pay for $7 monthly, GitHub has the biggest community and you can take advantage of it's public repositories, forks, etc.

Bitbucket: If you use other products from Atlassian like Jira or Confluence, Bitbucket works great with them.

GitLab: Everything that I care about (free private repository, number of private repositories, number of collaborators, etc.) are offered for free. This seems like the best choice for me.

Since January 7th, 2019, it is possible: unlimited free private repositories on GitHub!
... But for up to three collaborators per private repository.

Nat Friedman just announced it by twitter:

Today(!) we’re thrilled to announce unlimited free private repos for all GitHub users, and a new simplified Enterprise offering:

"New year, new GitHub: Announcing unlimited free private repos and unified Enterprise offering"

For the first time, developers can use GitHub for their private projects with up to three collaborators per repository for free.

Many developers want to use private repos to apply for a job, work on a side project, or try something out in private before releasing it publicly.
Starting today, those scenarios, and many more, are possible on GitHub at no cost.

Public repositories are still free (of course—no changes there) and include unlimited collaborators.

If you are a student you can get a free private repository at https://github.com/edu

Update

As noted in another answer, now there is an option for private repos also for simple users