Changing Git Account (User) in a Local Shell Environment

When you use two or more Git accounts on a single machine — for example, a personal GitHub account and a work GitHub/GitLab account — and need to push or pull as a specific identity, this guide covers every approach from a quick one-off override to a fully automated per-directory setup.

[01] Check Current Git Settings

Before making changes, confirm the active identity.

Check all config entries

git config -l

Figure 1. Sample output — git config -l git-config check-01

Figure 1. git config -l lists every config key from system, global, and local scopes. Look for user.name and user.email lines.

Check only user name and email

git config user.name
git config user.email

git-config check-02

Figure 2. Querying individual keys returns just the effective value — useful for a quick sanity check before committing.

Git resolves config in priority order: local (repo/.git/config) overrides global (~/.gitconfig) overrides system (/etc/gitconfig). The git config -l output shows which file each value comes from when you add --show-origin.

git config -l --show-origin

[02] Change Git Identity

Global change — applies to all repositories

Use --global to update ~/.gitconfig. This becomes the default identity for every repo that does not have a local override.

git config --global user.name "Your Name"
git config --global user.email "you@example.com"

git-config update

Figure 3. After running the two --global commands, git config user.name returns the new value immediately.

Local change — applies only to the current repository

Run the same commands without --global inside the repo directory:

git config user.name "Work Name"
git config user.email "work@company.com"

This writes to .git/config in the current repo and overrides the global value for that repo only. Useful when a single machine hosts both personal and work repositories.

One-off override for a single commit

If you only need to use a different identity once, set the environment variables inline:

GIT_AUTHOR_NAME="Other Name" GIT_AUTHOR_EMAIL="other@example.com" \
GIT_COMMITTER_NAME="Other Name" GIT_COMMITTER_EMAIL="other@example.com" \
git commit -m "feat: one-off commit as other identity"

[03] Automatic Per-Directory Account Switching with includeIf

When you have all personal repos under ~/personal/ and all work repos under ~/work/, Git’s includeIf directive can apply the correct identity automatically based on the repository path — no manual switching needed.

Step 1 — Create separate config files

# ~/.gitconfig-personal
[user]
    name = Personal Name
    email = personal@gmail.com

# ~/.gitconfig-work
[user]
    name = Work Name
    email = work@company.com

Step 2 — Add includeIf blocks to ~/.gitconfig

[user]
    name = Personal Name
    email = personal@gmail.com

[includeIf "gitdir:~/work/"]
    path = ~/.gitconfig-work

[includeIf "gitdir:~/personal/"]
    path = ~/.gitconfig-personal

When Git detects that the current repository lives under ~/work/, it loads ~/.gitconfig-work and its [user] section overrides the global default. The match is based on the .git directory path, so subdirectories are covered automatically.

Condition	Config applied
Repo is anywhere under `~/work/`	`~/.gitconfig-work`
Repo is anywhere under `~/personal/`	`~/.gitconfig-personal`
Repo is anywhere else	Global `~/.gitconfig` default

[04] SSH Config for Multi-Account Authentication

Changing user.name and user.email only affects commit authorship — it does not change which SSH key is used to authenticate with the remote. For full account isolation (so pushes go to the correct GitHub/GitLab account), configure SSH aliases.

Step 1 — Generate separate SSH keys

ssh-keygen -t ed25519 -C "personal@gmail.com" -f ~/.ssh/id_ed25519_personal
ssh-keygen -t ed25519 -C "work@company.com"   -f ~/.ssh/id_ed25519_work

Step 2 — Add public keys to each Git host account

Copy each .pub file content and add it under Settings → SSH Keys on GitHub/GitLab for the respective account.

Step 3 — Configure ~/.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

Step 4 — Use the alias in remote URLs

# Personal repo
git remote set-url origin git@github-personal:username/repo.git

# Work repo
git remote set-url origin git@github-work:org/repo.git

Git will now use the correct SSH key automatically when pushing or pulling, regardless of the global identity settings.

[05] Troubleshooting

Symptom	Likely Cause	Fix
Commits still show old name/email after `--global` change	Local repo config overrides global	Run `git config user.name` inside the repo — if it shows the old value, remove the local override with `git config --unset user.name`
`includeIf` not applying the expected identity	Path condition does not match — trailing slash required	Ensure the path ends with `/`: `gitdir:~/work/` not `gitdir:~/work`
Push rejected with “Permission denied (publickey)”	SSH key for target account not loaded	Run `ssh -T git@github-personal` to test the alias; add the key with `ssh-add ~/.ssh/id_ed25519_personal`
Author of past commits is wrong	Identity was misconfigured when commits were made	For local branches not yet pushed, use `git rebase` to rewrite; for public commits, coordinate with repo maintainers before rewriting history
`git config -l` shows duplicate user.name	Both global and local scopes have a value	The local value wins; decide which scope should own the setting and remove the other with `--unset`

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