Warmup gradually builds your mailboxes' sending reputation before you start cold outreach — and keeps it healthy once campaigns are running.

No. Every mailbox is delivered fresh — Maildoso does not sell "pre-warmed," "already warmed up," or otherwise reputation-built mailboxes at any volume, including bulk/agency orders. We also do not run warmup automatically or on your behalf (see below).
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The email accounts are new, so you'll need to start the warmup process using a third-party email sequencer; it takes about two weeks to build up your reputation, after which you can scale up your email campaigns.

Once your mailboxes are set up, run warmup for roughly two weeks so the mailboxes build a healthy history before you scale into real campaigns. Keep warmup running continuously — pausing it interrupts that reputation-building. Wait until the health score of your mailboxes exceeds 90% before starting email campaigns. This ensures that your email accounts are fully prepared for outreach and reduces the risk of deliverability issues. You can track this progress on the Insights page — see Understanding your Warmup & Deliverability Insights.

Yes. Buying mailboxes does not automatically start warmup, and Maildoso does not run a background or managed warmup pool on your behalf. Warmup runs through the sequencer you connect your mailboxes to (for example Instantly or Plusvibe — both have good warmup pools). Turn warmup on inside that tool and keep it running.

To optimize the warm-up process, use the following settings in Instantly for Maildoso SMTP mailboxes:

Some tools cap warmup below 80 — Plusvibe and EmailBison max out at 50/day. In that case use their maximum and lower your campaign volume to roughly 10/day to keep the ratio right.

For Maildoso SMTP mailboxes, set the warmup volume directly to 80 emails per mailbox per day with the daily increment disabled, rather than ramping up gradually. Then, after the 14-day warmup, cap campaign sending at 15 emails per mailbox per day, including follow-ups.

The 15/day is a campaign limit, not a replacement for warmup. Once campaigns start, warmup stays on at 80/day alongside them — warmup is not a phase you finish and switch off. Keeping a high warmup-to-cold-email ratio is what protects the mailbox; the most common cause of deliverability problems we see is the opposite pattern, low warmup with high campaign volume. If you need to change one of the two numbers, reduce campaign volume rather than warmup. See What's the daily email limit per email account? for the exact limits, including Google Workspace and the 100/day campaign cap.

If a third-party tool (Mailivery, Mailwarm, etc.) reports a high spam percentage on mailboxes that have only been warming up and have sent zero campaign emails, the most common cause is a weak warmup pool in that tool — not a problem with your domain or mailboxes.

Two things to keep in mind: (1) our dashboard reputation and a single third-party seed-list placement test measure different things, and a one-off test is a snapshot that can vary; (2) Gmail is much stricter than Outlook, so a weak pool often shows up as poor Gmail placement specifically. If you're seeing this, switch warmup to a stronger pool such as Instantly or Plusvibe at roughly 50–80/day — placement typically recovers within a few days. If it persists, contact support so our deliverability specialist can review the account.

The Maildoso AI Premium Warmup add-on is no longer available for new subscriptions — you can't purchase it if you don't already have it. If you're an existing subscriber, your premium warmup continues as normal; you don't need to do anything differently. If you don't have this subscription, warm your mailboxes through your sequencer as described above.

📹 How to Scale to 100K Emails/Month Without Killing Deliverability — how teams set up infrastructure, warm mailboxes, and spam-test to scale volume safely.

Related: Warmup Filters.