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Multi-Account GitHub SSH Setup (Clean and Safe)

This guide explains how to configure multiple GitHub accounts on the same machine using SSH so that each repository pushes with the correct account.

Example accounts:

This prevents accidental pushes with the wrong identity and ensures GitHub Actions shows the correct actor.

1. Generate a Separate SSH Key for Each Account

Create one SSH key per GitHub account.

Personal account:

ssh-keygen -t ed25519 -C "personal_name"

Save as:

~/.ssh/id_ed25519_personal

Organization account:

ssh-keygen -t ed25519 -C "organization_name"

Save as:

~/.ssh/id_ed25519_organization

Resulting directory structure:

~/.ssh/
  id_ed25519_personal
  id_ed25519_personal.pub
  id_ed25519_organization
  id_ed25519_organization.pub

2. Add Each Key to the Correct GitHub Account

Copy the public keys:

cat ~/.ssh/id_ed25519_personal.pub
cat ~/.ssh/id_ed25519_organization.pub

Add them to GitHub:

Account personal_name
Settings → SSH and GPG keys → New SSH key
Paste:

id_ed25519_personal.pub

Account organization_name
Settings → SSH and GPG keys → New SSH key
Paste:

id_ed25519_organization.pub

3. Configure SSH Aliases

Edit or create:

~/.ssh/config

Example configuration:

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

Host github-organization
  HostName github.com
  User git
  IdentityFile ~/.ssh/id_ed25519_organization
  IdentitiesOnly yes

This creates two SSH aliases:

Each alias uses a different SSH key.

4. Test Authentication

Verify each account works.

Test personal account:

ssh -T github-personal

Expected output:

Hi personal_name! You've successfully authenticated

Test organization account:

ssh -T github-organization

Expected output:

Hi organization_name! You've successfully authenticated

5. Configure Repository Remotes

Set the repository remote to the correct SSH alias.

Repositories that should push as personal_name:

git remote set-url origin git@github-personal:OWNER/REPO.git

Repositories that should push as organization_name:

git remote set-url origin git@github-organization:OWNER/REPO.git

Example:

git remote set-url origin git@github-organization:organization_name/myrepo.git

This controls commit metadata (author name/email).

For organization repositories:

git config user.name "organization_name"
git config user.email "organization_email@example.com"

For personal repositories:

git config user.name "personal_name"
git config user.email "personal_email@example.com"

7. Verify the Setup

Check the configured remote:

git remote -v

Example output:

origin git@github-organization:organization_name/repo.git

Push a commit and verify on GitHub:

Result

Repository type SSH alias Push actor
personal repos github-personal personal_name
organization repos github-organization organization_name

This setup ensures: