Acceptable Use Policy

Last updated April 2026.

This Acceptable Use Policy ("AUP") governs your use of Mailbird. We keep it short. Don't use Mailbird to do things that are harmful, illegal, or that damage the deliverability of other Mailbird users.

What you may not do

Spam and unwanted email

• Send unsolicited commercial email in violation of CAN-SPAM, the EU ePrivacy Directive, GDPR, CASL, or any other applicable law.
• Send to addresses obtained through scraping, purchase, rental, or any other means without explicit opt-in.
• Send without a working unsubscribe mechanism on bulk or marketing email.
• Forge or misrepresent the From, Reply-To, Sender, or any other header in a way that misleads recipients.

Fraud and impersonation

• Send phishing emails, including credential-harvesting messages or impersonation of any person, organisation, or brand you don't represent.
• Operate a business email compromise scheme or any other fraud.

Harassment and harm

• Send threats, harassment, hate speech, or content that incites violence.
• Send sexually explicit material to recipients who have not consented to it; never send any such material involving minors.

Illegal content and activities

• Distribute or facilitate distribution of malware, viruses, ransomware, or any malicious code.
• Send anything that infringes copyright, trademark, or other intellectual property.
• Conduct any activity that violates applicable law in the jurisdiction of the sender, the recipient, or where Mailbird operates.

Service abuse

• Attempt to scrape, reverse engineer, or extract data from the Service beyond what the API exposes.
• Resell or sublicense the Service to third parties as a packaged product. (You may use Mailbird internally to send mail on behalf of customers of your own product — that's normal SaaS use, not resale.)
• Probe, scan, or test the vulnerability of the Service or attempt to bypass security controls.
• Use Mailbird to attack or disrupt third parties.

What we may do if you violate this policy

• Warning. For minor or ambiguous violations, we'll reach out and give you a chance to fix it.
• Suspension. For ongoing or material violations, we may suspend your account temporarily.
• Termination. For severe or repeat violations, we may terminate your account immediately.
• Cooperation with law enforcement. For violations involving fraud, child sexual abuse material, malware distribution, or threats of violence, we will cooperate with appropriate legal authorities.

We reserve the right to take any of these actions without prior notice when the violation is serious or ongoing.

Reporting abuse

To report abuse of Mailbird's services — for example, if you have received spam or phishing from a Mailbird-hosted server — email abuse@mailbird.io. Please include full headers of the offending message. We act on reports promptly.

Questions

If you're unsure whether something is acceptable, ask first: support@mailbird.io. We'd rather have a quick conversation than discover a problem later.