Disclosure
Affiliate disclosure
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Spamcheck is free. Some links to email services are affiliate links: if you sign up through them we may earn a commission at no extra cost to you. We only recommend a service when it actually solves the deliverability problem we detect — payouts never decide what we recommend.
Our affiliate partners
| Service | What it helps with |
|---|---|
| Postmark | Transactional email with excellent deliverability and built-in DKIM/DMARC setup. |
| Brevo | Marketing + transactional sending with guided domain authentication. |
| MailerSend | Developer-friendly transactional email with a clear domain-auth wizard. |
| Instantly | Cold-email platform with automated domain warm-up. |
| EmailListVerify | Clean your list to cut bounces and protect sender reputation. |
| Smartlead | Cold-email sending with built-in inbox warm-up and rotation. |
| Warmup Inbox | Automated inbox warm-up to build sender reputation on a new domain. |
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