Migrate repo from GitLab to GitHub Full blog post @ http://ruby.zigzo.com/2015/03/23/moving-from-gitlab-to-github/

migrate_repo.sh

# Assume we are in your home directory
cd ~/

# Clone the repo from GitLab using the `--mirror` option
$ git clone --mirror [email protected]:mario/my-repo.git

# Change into newly created repo directory
$ cd ~/my-repo.git

# Push to GitHub using the `--mirror` option.  The `--no-verify` option skips any hooks. 
$ git push --no-verify --mirror [email protected]:mario/my-repo.git

# Set push URL to the mirror location
$ git remote set-url --push origin [email protected]:mario/my-repo.git

# To periodically update the repo on GitHub with what you have in GitLab
git fetch -p origin
git push --no-verify --mirror

Use HTTPS urls instead of SSH url if you are having the error about publickey. That should do the same thing.

So instead of [email protected]:mario/my-repo.git use https://your-gitlab-site.com:mario/my-repo.git

Yes, this works perfect!

Anyone finding this in 2020+, there is a very convenient import method from Gitlab now as well:
Click [+] in the Gitlab header > "New project" > Tab "Import project" > Select "Gitlab"

After authorization on GitHub you'll be taken to https://gitlab.com/import/github/status for easy import management.