← Back to MailBridge

Privacy Policy

Last updated: October 24, 2026

1. Introduction

MailBridge is a service operated by Astartes ("MailBridge", "we", "us", "our"). We provide a tool that helps users migrate email data between email providers. This Privacy Policy explains what information we collect, how we use it, and how we protect it when you use our service at mailbridge.website (the "Service").

By using the Service, you agree to the collection and use of information in accordance with this policy.

2. Information We Collect

We collect only the information necessary to perform email migrations:

• Account identifiers: Your email address and display name from connected email providers (e.g. Gmail, Outlook), used to identify your accounts in the dashboard.
• OAuth tokens: Access and refresh tokens granted by your email provider. These are encrypted at rest and used solely to authenticate API requests on your behalf during migration.
• Message identifiers: Message-ID headers and provider message IDs, used for idempotency tracking and duplicate prevention. These are routing identifiers, not message content.
• Migration metadata: Job status, chunk progress, message counts, message sizes, and timestamps. This is operational data required to run and monitor migrations.
• Authentication data: Your Supabase Auth session (email/password or OAuth) used to access the MailBridge dashboard.

3. Email Content and Pass-Through Handling

MailBridge is a pass-through service. Email content is not a product data store for us. We do not index, analyse, profile, or mine your email content, and we never use it for advertising or to train any model.

During a migration, message bytes move from your source provider to your destination provider. In the ordinary case they are streamed directly and never written to disk. For unusually large messages (over 20 MB), the message is buffered to a temporary file on the migration worker's local disk to keep memory bounded, then streamed to the destination and deleted immediately. That buffer is local to the worker container, is not uploaded to any third-party storage service, and is destroyed with the container.

We do not retain copies of your email content. We do not store message bodies or attachments in our application database.

4. Information We Do NOT Collect

• Passwords: We never see or store your email passwords. All authentication is handled through OAuth flows managed by your email provider.
• Contact lists, calendars, or files: We do not request or access data outside the email scope required for migration.
• Advertising or tracking data: We do not use third-party advertising or cross-site tracking.

5. How We Use Your Information

We use the collected information exclusively to:

• Authenticate with your email providers to read from your source account and write to your destination account.
• Plan, execute, and monitor email migrations on your behalf.
• Prevent duplicate messages from being delivered on re-runs.
• Display migration progress and status in your dashboard.
• Send you a notification email when a migration completes.
• Maintain the security, reliability, and abuse prevention of the Service.

We do not use your information for advertising, profiling, or any purpose unrelated to the Service.

6. Human Access to Your Data

MailBridge staff do not read your email content in the course of operating the Service. Access to the underlying infrastructure is limited to what is required to operate and secure the Service, and is protected by least-privilege access controls.

We may access account-level metadata (such as job status and error records) to diagnose a failure you have reported to us. We will only access message content with your explicit consent, or where we are compelled to do so by law.

7. Data Storage and Security

• Encryption at rest: OAuth tokens are encrypted using AES-256-GCM before being stored in our database.
• Encrypted transit: All data is transmitted over TLS/HTTPS.
• Database: Metadata is stored in Supabase (PostgreSQL) with row-level security policies ensuring users can only access their own data.
• Access control: Administrative access is limited to the operator and protected by least privilege.

8. Third-Party Services

MailBridge uses the following service providers to operate. Each acts as a processor on our behalf, and none may use your data for their own purposes:

• Google (Gmail API): Used to read and write Gmail messages during migration. Subject to Google's Privacy Policy.
• Microsoft (Microsoft Graph): Used to read and write Outlook/Microsoft 365 messages during migration. Subject to Microsoft's Privacy Statement.
• Supabase: Provides authentication, database, and realtime infrastructure. Subject to Supabase's Privacy Policy.
• Trigger.dev: Provides the background worker infrastructure used to execute migrations. Subject to Trigger.dev's Privacy Policy.
• Vercel: Provides web hosting and deployment infrastructure. Subject to Vercel's Privacy Policy.
• Resend: Used to send transactional emails (migration completion notifications). Subject to Resend's Privacy Policy.
• Stripe: Used to process payments for paid migrations. Subject to Stripe's Privacy Policy. We do not receive or store your full card number.

We do not sell your personal information, and we do not share it with third parties for their own purposes.

9. Your Rights

You have the right to:

• Access: View all data associated with your account through the MailBridge dashboard.
• Disconnect: Revoke MailBridge's access to any connected email account at any time from the dashboard, which deletes the stored OAuth tokens.
• Revoke at the provider: You can also revoke MailBridge's access directly from your Google Account at Google's "Third-party apps & services" page, or from your Microsoft account at Microsoft's app permissions page.
• Delete: Request full deletion of your account and all associated data by contacting us at the email below.
• Export: Request a copy of the metadata we hold about your account.

10. Data Retention

• OAuth tokens: Retained until you disconnect the account or delete your MailBridge account.
• Migration metadata: Retained so you can review past migrations while your account is active.
• Error records: Retained for 30 days for debugging purposes.

When you disconnect an account or delete your MailBridge account, the associated tokens and personal data are permanently removed within 30 days.

11. Children's Privacy

The Service is not intended for use by individuals under the age of 16. We do not knowingly collect personal information from children.

12. Changes to This Policy

We may update this Privacy Policy from time to time. If we make material changes, we will notify you by email or by posting a notice on the Service. Your continued use of the Service after changes take effect constitutes acceptance of the updated policy.

13. Contact Us