Warmbox
Warmbox is an email warm-up service that connects to an inbox and automatically sends and interacts with messages to raise sender reputation and email delive…
What Warmbox is
Warmbox is an email warm-up service that connects to an inbox and automatically sends and interacts with messages to raise sender reputation and email deliverability. Its actions include removing warm-up emails from spam, opening and bookmarking them, and replying to some. Users can select growth, flat, random, or custom settings and configure scheduling, timing, daily volume, and reply rate. The dashboard reports sent emails, reply rate, spam score, warm-up schedule, and inbox reputation. Warmbox describes a private network of more than 35,000 inboxes spanning more than 100 countries. Listed providers include Gmail, Outlook, Yahoo, SendGrid, Sendinblue, SMTP, Amazon SES, Mailgun, iCloud, AOL, Zoho, and Yandex. A separate checker audits IP and domain blacklist status and examines SPF, DKIM, and DMARC across more than 120 checkpoints; its feature page calls it free. The Solo plan costs $15 a month with yearly billing and includes one inbox, 50 emails per day, and one member. Monthly Solo billing costs $19 a month. Warmbox estimates initial results usually take 15–30 days of uninterrupted warming, depending on the address and provider.
Good
- Automates email sending, opening, and some replies.
- Offers configurable schedules, daily volume, and reply rates.
- Dashboard tracks spam score and inbox reputation.
- Checker reviews blacklist status and SPF, DKIM, and DMARC.
Watch out
- No free plan is listed.
- Solo yearly plan covers one inbox and 50 emails daily.
- Initial results may take 15–30 days of uninterrupted warming.
Who it suits
Warmbox suits individuals and teams seeking automated inbox warming and deliverability monitoring. Its listed providers and agency workspaces may be relevant to organizations managing multiple inboxes or brands.
Verdict
Warmbox combines inbox warming controls with reputation monitoring and a separate DNS and blacklist checker. Consider its per-plan inbox and daily sending limits, along with the estimated warming period.
Plans and prices
From Warmbox's own pricing page, checked 8 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Solo (yearly billing) | $15 a month | 1 inbox warm-up · 50 emails/day · 1 member · Premium support · Yearly billing |
| Solo (monthly billing) | $19 a month | 1 inbox warm-up · 50 emails/day · 1 team member · Premium support · Monthly billing |
| Start-up (yearly billing) | $69 a month | 3 inbox warm-up · 250 emails/day · 3 team members · Premium support · Yearly billing |
| Start-up (monthly billing) | $79 a month | 3 inbox warm-up · 250 emails/day · 3 team members · Premium support · Monthly billing |
| Growth (yearly billing) | $139 a month | 6 inbox warm-up · 500 emails/day · 6 team members · Enterprise support · Yearly billing |
| Growth (monthly billing) | $159 a month | 6 inbox warm-up · 500 emails/day · 6 team members · Enterprise support · Monthly billing |
| Team | Priced on request | Custom needs · Contact for pricing |
The facts
Each one read from Warmbox's own pages, with the date it was checked.
What it does
- Agency features
- The product page says users can add inboxes and team members and create dedicated brand workspaces for agencies.checked 8 Oct 2026
- DNS and blacklist checker
- Its checker audits IP and domain blacklist status and inspects SPF, DKIM, and DMARC using more than 120 checkpoints; the feature page calls it free.checked 8 Oct 2026
- Email providers
- Listed providers include Gmail, Outlook, Yahoo, SendGrid, Sendinblue, SMTP, Amazon SES, Mailgun, iCloud, AOL, Zoho, and Yandex.checked 8 Oct 2026
- Mailbox data handling
- Warmbox says it processes service-generated warm-up emails and technical deliverability signals, not the content of users’ other correspondence, and does not sell this data or use it for advertising.checked 8 Oct 2026
- Monitoring
- The dashboard reports sent emails, reply rate, spam score, warm-up schedule, and inbox reputation.checked 8 Oct 2026
- Network
- Warmbox describes a private network of more than 35,000 inboxes spanning more than 100 countries.checked 8 Oct 2026
- Privacy compliance
- The pricing FAQ states that Warmbox meets GDPR and CCPA requirements for personal data storage and use.checked 8 Oct 2026
- Purpose
- Warmbox says it automatically sends and interacts with emails from a connected inbox to raise sender reputation and email deliverability.checked 8 Oct 2026
- Security
- The privacy policy describes TLS and at-rest encryption, encrypted mailbox credentials, access controls, production access monitoring, backups, independent penetration tests, and SOC 2 Type II compliance.checked 8 Oct 2026
- Support
- The pricing FAQ says all plans include in-app chat support and an online help center; some sales subscribers may qualify for personalized onboarding and an account manager.checked 8 Oct 2026
- Warm-up actions
- It sends warm-up emails, removes them from spam, opens and bookmarks them, and replies to some messages.checked 8 Oct 2026
- Warm-up controls
- Warm-up options include growth, flat, random, and custom settings, with scheduling and configurable timing, daily volume, and reply rate.checked 8 Oct 2026
- Warm-up duration
- Warmbox estimates that first results usually take 15–30 days of uninterrupted warming, depending on the email address and provider.checked 8 Oct 2026
The company
- Headquarters
- Tallinn, Estoniachecked 28 Sep 2026
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