As a Mastodon instance administrator, you may want to control who can join your community to prevent spam, bots, or unwanted users. Mastodon provides a built-in sign-up approval workflow that lets you review and approve or reject new account requests before they gain access. This article explains how to enable the approval mode, manage pending applications, and handle common issues during the process. By the end, you will be able to set up a moderated registration system that keeps your instance secure and focused on its intended audience.
Key Takeaways: Mastodon Sign-Up Approval for Admins
- Administration > Server Settings > Registrations: Enable the “Require approval for new sign-ups” toggle to activate the approval workflow.
- Administration > Pending Accounts: Review, approve, or reject new user applications with a single click from this panel.
- Custom email notifications: Inform applicants about the approval status using Mastodon’s built-in email templates or by sending manual replies.
How Mastodon Sign-Up Approval Works
Mastodon’s approval workflow is a registration gate that sits between the public sign-up form and account creation. When enabled, new users who fill out the registration form do not get immediate access. Instead, their account is placed in a pending state. The admin receives a notification, and the applicant sees a message that their request is awaiting review.
This feature is part of the server’s registration settings under the Administration panel. You can combine it with other restrictions such as email domain whitelists, CAPTCHA, or custom text fields in the sign-up form. The approval mode does not affect existing users or users who join via invitations if you have that feature enabled separately.
The pending account list shows each applicant’s username, email address, IP address, and the date of the request. You can also view any custom text they entered if you added a custom field to the registration form. This information helps you decide whether to approve or reject the application.
Prerequisites for Using the Approval Workflow
Before you enable the approval mode, ensure the following conditions are met:
- You have admin-level access to the Mastodon instance, typically the account that created the server or an account with the Admin role.
- Registration is set to “Anyone can sign up” in the server settings. The approval mode is a sub-option that only appears when open registration is enabled.
- Your instance’s email system is configured correctly so that you receive notifications about pending accounts and can send approval or rejection emails to applicants.
Steps to Enable and Manage Sign-Up Approval
Follow these steps to activate the approval workflow and process pending applications.
- Log in to your Mastodon admin account
Open your instance’s web interface and sign in with an account that has the Admin role. Only admin accounts can access the server settings. - Navigate to Administration > Server Settings > Registrations
Click the hamburger menu (three horizontal lines) in the top-right corner, select “Administration,” then “Server Settings,” and finally the “Registrations” tab. - Enable the “Require approval for new sign-ups” toggle
Find the checkbox labeled “Require approval for new sign-ups” and check it. The setting is located directly below the registration mode selector. If the checkbox is grayed out, ensure that “Anyone can sign up” is selected above it. - Click “Save changes”
Scroll to the bottom of the page and click the blue “Save changes” button. The approval workflow is now active. New sign-ups will be held for review. - Review pending accounts
Go to Administration > Pending Accounts. This page lists all applicants waiting for approval. Each row shows the username, email, IP address, sign-up date, and any custom text they submitted. - Approve or reject an applicant
Click the “Approve” button next to an applicant to activate their account immediately. Click “Reject” to deny the request. Optionally, you can click the username to view more details before making a decision. Rejected applicants receive an email notification if your instance’s email system is working. - Send a custom message (optional)
If you want to communicate with an applicant before or after approval, use the email address listed in the pending account details. Mastodon does not provide an in-app messaging system for this purpose, so you must send emails manually from your own email client.
Approving Multiple Accounts at Once
If you have many pending applications, you can approve them in bulk. On the Pending Accounts page, use the checkbox at the top of the table to select all visible applicants. Then click the “Approve selected” button that appears. This action approves every selected account in one batch. Rejecting multiple accounts works the same way with the “Reject selected” button.
Common Issues with the Approval Workflow
Pending Accounts Not Appearing in the Admin Panel
If you have enabled the approval mode but no pending accounts show up, check the following:
- Confirm that the “Require approval for new sign-ups” checkbox is still checked. Sometimes browser caching or a failed save can revert the setting.
- Verify that registration mode is set to “Anyone can sign up.” If it is set to “Only people with an invitation can sign up,” the approval checkbox has no effect.
- Ask a test user to attempt registration from a different browser or incognito window. If the registration form does not display a pending message, the workflow may not be active.
Applicants Not Receiving Approval or Rejection Emails
Mastodon sends automated emails when an account is approved or rejected. If applicants do not receive these emails, the instance’s email delivery system may be misconfigured. Check the following:
- Verify that SMTP settings are correct in the .env.production file. Common issues include wrong port numbers, missing authentication credentials, or incorrect TLS settings.
- Test email delivery by sending a test email from the Administration > Server Settings > Email tab. If the test fails, fix the SMTP configuration before relying on approval notifications.
- Check the spam or junk folder of the applicant’s email account. Some email providers may block automated messages from unknown servers.
Accidentally Rejecting a Legitimate User
If you reject an account by mistake, there is no undo button in the admin panel. The rejected user must sign up again with a new email address. To prevent this, always review the applicant’s details carefully before clicking “Reject.” You can also contact the user via email before making a final decision if their application is unclear.
Approval Workflow vs. Invitation-Only Registration
| Item | Approval Workflow | Invitation-Only Registration |
|---|---|---|
| Registration process | User fills out a public form and waits for admin approval | User must receive an invitation link from an existing member or admin |
| Admin effort | Review and approve or reject each applicant manually | Generate and distribute invitation links; no per-user review |
| Scalability | Works well for small to medium communities with moderate sign-up volume | Better for very small private communities or servers with strict membership control |
| User experience | Applicants may wait hours or days for approval; they see a pending message | Users only see the sign-up form if they have a valid invitation link |
The approval workflow is a middle ground between fully open registration and invitation-only access. It gives you visibility into who is joining while still allowing anyone to discover and request access to your instance. Invitation-only registration is more restrictive and requires you to actively manage a pool of invitation tokens.
You can now manage new user sign-ups with the approval workflow. Start by enabling the toggle in Server Settings > Registrations and then check the Pending Accounts page regularly. For stricter control, consider combining the approval mode with an email domain whitelist or a custom registration question. This approach helps you maintain a focused community without blocking legitimate users entirely.