The rules for using MailKite — accounts, acceptable use and anti-spam, plans and billing, service levels, and the legal bits.
Effective date: 2026-06-24
These Terms of Service ("Terms") govern your access to and use of MailKite (the "Service"). By creating an account or using the Service, you agree to these Terms. If you're using MailKite on behalf of an organization, you represent that you're authorized to bind it.
Our Privacy Policy and SLA are part of these Terms.
MailKite receives inbound email for domains you control and delivers it to your webhook, and sends outbound email through our API. You're responsible for the domains you connect, the DNS records you set, the endpoints you point us at, and the content you send and receive.
Keep your credentials, API keys, and webhook signing secrets secret. You're responsible for activity under your account and keys. Verify the x-mailkite-signature header on inbound webhooks so you only act on genuine events. Tell us promptly at support@mailkite.dev if you suspect unauthorized use.
You agree not to use MailKite to:
We may throttle, suspend, or terminate accounts that violate this section or threaten the deliverability, security, or integrity of the platform. We may act immediately for egregious abuse.
Paid plans are billed in advance on a recurring basis. One quota covers both inbound and outbound messages; usage above your plan is metered at the plan's overage rate rather than hard-cut. Domains are free; you only pay for volume.
If you register a domain through MailKite, you authorize the charge shown before you confirm — the registrar's price plus payment processing and a small flat fee — and you agree to the registrar's terms. Domain-registration charges are non-refundable once the registration is placed.
Fees exclude taxes, which you're responsible for. Failure to pay may result in suspension. You can cancel anytime; cancellation stops future renewals and does not refund the current period except where required by law.
Optional inbox-agent and assistant features process your message content with our AI provider to produce results you request. You may bring your own model key. You're responsible for how you use AI output; it may be imperfect and should be reviewed before relying on it. AI actions are billed as described on our pricing page unless you use your own key.
Paid plans are backed by our Service Level Agreement, including a 99.9% monthly uptime commitment and service credits. The Free plan is provided on a best-effort basis with no uptime commitment. See the SLA for full terms.
You retain all rights to the email and data you send and receive. You grant us only the limited rights needed to operate the Service for you — to receive, process, store (per your retention settings), and deliver your mail. Our handling of your data is described in the Privacy Policy, including per-domain zero-retention and at-rest encryption options.
The Service relies on third parties (such as Cloudflare, Stripe, our AI provider, and domain registrars). Your use may be subject to their terms, and we're not responsible for their acts or outages beyond our reasonable control.
The Service is provided "as is" and "as available" without warranties of any kind, whether express or implied, including merchantability, fitness for a particular purpose, and non-infringement. We don't warrant that the Service will be uninterrupted or error-free beyond the commitments in the SLA, or that every message will be delivered, given the realities of the email ecosystem.
To the maximum extent permitted by law, MailKite will not be liable for any indirect, incidental, special, consequential, or punitive damages, or for lost profits, revenue, or data. Our total liability for any claim arising out of or relating to the Service is limited to the amount you paid us for the Service in the three months before the event giving rise to the claim. Service credits under the SLA are your sole remedy for downtime.
You agree to indemnify and hold MailKite harmless from claims arising out of your content, your use of the Service, or your violation of these Terms or applicable law (including anti-spam law).
You may stop using the Service and close your account at any time. We may suspend or terminate access for violation of these Terms, non-payment, or to protect the Service. On termination, your right to use the Service ends and we may delete your data after a reasonable period, subject to the Privacy Policy and law.
We may update these Terms from time to time. Material changes will be announced to your account contact email. Continued use after changes take effect means you accept them.
Questions about these Terms: support@mailkite.dev.
See also our Privacy Policy and SLA.