How to: Best Practices for Working with Multiple GitHub Accounts

One SSH key per account. One alias per host. No manual switching.

2026-02-28 · Stefan Wendel · Claude Sonnet 4.6

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Every developer who uses multiple GitHub accounts — a personal one, one for their employer, one for a side project — knows the problem: Git doesn’t ask which account you mean. It just picks the first matching key. The result: pushes under the wrong account, rejected authentications, or the classic blunder of landing a private commit under your company account.

The solution is straightforward and permanent: one SSH key per account, configured via host aliases in ~/.ssh/config.

The Setup

1. Generate SSH keys

Create a dedicated Ed25519 key for each account:

ssh-keygen -t ed25519 -C "you@example.com"  -f ~/.ssh/id_ed25519_personal
ssh-keygen -t ed25519 -C "you@company.com"  -f ~/.ssh/id_ed25519_work
ssh-keygen -t ed25519 -C "you@project.com"  -f ~/.ssh/id_ed25519_project

The -f flag sets the filename — all keys end up cleanly separated in ~/.ssh/.

2. Add public keys to GitHub

For each account:

1. Log in to GitHub
2. Settings → SSH and GPG keys → New SSH key
3. Paste the contents of the respective .pub file

cat ~/.ssh/id_ed25519_personal.pub   # for account 1
cat ~/.ssh/id_ed25519_work.pub       # for account 2
cat ~/.ssh/id_ed25519_project.pub    # for account 3

3. Create ~/.ssh/config

Host github-personal
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_ed25519_personal

Host github-work
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_ed25519_work

Host github-project
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_ed25519_project

Each Host entry is an alias for github.com — with a fixed key assigned to it.

4. Test the connections

ssh -T git@github-personal
# Hi username-personal! You've successfully authenticated...

ssh -T git@github-work
# Hi username-work! You've successfully authenticated...

Connecting repos correctly

Instead of github.com in the remote URL, just use the alias:

# New repo:
git remote add origin git@github-work:company/repo.git

# Switch an existing remote:
git remote set-url origin git@github-personal:username/repo.git

SSH looks up the alias in the config on connect, finds the matching entry, and automatically picks the right key — no further action needed.

Why this works

~/.ssh/config is a routing table for SSH connections. When Git connects to git@github-work:..., SSH matches the host github-work, reads the assigned IdentityFile, and authenticates with exactly that key — regardless of what other keys exist on the system.

The result: every repo pushes with the correct GitHub account automatically, as long as the remote URL uses the right alias. No ssh-add, no environment switching, no risk of committing under the wrong account.

The Bottom Line

Multiple GitHub accounts aren’t an edge case — they’re the normal situation for anyone who develops professionally. The key is to encode the separation once, cleanly, in ~/.ssh/config. After that, everything runs on autopilot.

Configure once. Never think about it again.

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Do you use multiple GitHub accounts? What pitfalls have you run into?