Recommended warmup and campaign settings per mailbox:
Maildoso SMTP mailboxes
Warmup: 80 emails/day from day one, reply rate 35%, increment per day / slow ramp-up disabled. The exact reply-rate figure matters little — anything between 30% and 45% is fine; the volume and the disabled ramp-up are what matter.
Campaign (after the 14-day warmup): max 15 emails/day per mailbox, including follow-ups. Once the 14 days of warmup at 80/day are done you can start at 15/day right away. A campaign slow ramp-up (5/day in week 1, 10/day in week 2, then 15) is optional, not required, as long as warmup is running at 80/day.
Google Workspace mailboxes
Warmup: 25 emails/day, reply rate 30%, increment per day 2–3.
Campaign (after the 14-day warmup and slow ramp-up): max 10 emails/day per mailbox, including follow-ups.
If your warmup tool caps warmup lower than these numbers, use its maximum from day one and lower your campaign volume to match — for example Plusvibe and EmailBison cap warmup at 50/day, in which case set warmup to 50, disable the tool's slow ramp-up, and cap campaign sending at around 10/day rather than 15.
A tool's cap is not the reason a mailbox gets flagged for low warmup. When we flag mailboxes as needing more warmup, it is because their actual warmup volume is below our recommendation — typically well under 50/day (for example 10, 20 or 40 a day). Check the per-mailbox numbers first: a mailbox running at 20 warmup emails a day in Plusvibe is not limited by the 50/day cap, it is under-using it. Raise those mailboxes to the tool's maximum; the cap only becomes relevant once you are already at it.
These are Maildoso's official numbers. If you've read different figures in a blog post, in a sequencer's default template, or in a sequencer's own AI recommendation, use the numbers on this page — sequencers recommend generic settings for every mailbox provider, these are the settings tuned for ours.
Warmup runs alongside your campaigns, not instead of them
The 15/day figure is a campaign (cold email) limit. It does not replace your warmup volume — once the 14-day warmup is done and you start sending campaigns, warmup stays on at 80/day alongside the campaign. Warmup is not a phase you complete and switch off.
This ratio is deliberate. A high warmup-to-cold-email ratio is what keeps a mailbox healthy — the most common cause of deliverability problems we see is exactly the opposite pattern: low warmup combined with high campaign volume. If you have to change one of these numbers, lower the campaign volume; don't cut warmup.
If your emails are landing in spam
Pause campaigns on affected mailboxes and continue warming them up for about a week.
Reassess inbox placement after warmup and gradually ramp up sending volumes.
Ensure you adhere to the recommended daily limits and reply rates for your mailbox type.
Monitor for improvements and adjust configurations as needed. If placement doesn't recover, book a Deliverability Audit from the top-right button in your dashboard.
The 100/day limit
A mailbox is automatically deactivated if its total sending exceeds 100 emails/day. The total counts everything the mailbox sends — warmup, campaign emails, follow-ups and replies combined. With the recommended 80 warmup + 15 campaign you're at about 95/day, which is why those numbers leave headroom under the cap.
Two things to keep in mind so your sending is measured correctly:
Follow-ups count inside your 15/day campaign cap, not on top of it.
Set up Warmup Filters (Master Inbox page → set up warmup filter → pick your provider or add a custom warmup tag) so your warmup traffic is correctly identified as warmup in your Insights. See Warmup Filters.
Occasional spam or inbox-placement tests don't meaningfully affect your reputation and don't need to be budgeted for — only excessive testing (in the range of 20–30 tests per mailbox per day) becomes a problem.
Limits are per mailbox, not per domain
All sending limits, including the warmup and operational limits, are applied per mailbox, not per domain. For example, if a domain has four mailboxes, the total campaign capacity for that domain is 4 × 15 = 60 emails/day.
This also means domain-level volume scales with how many mailboxes you put on each domain:
8 SMTP mailboxes on a domain → up to 120 campaign emails/day from that domain.
50 SMTP mailboxes on a domain → up to 750 campaign emails/day from that domain.
We recommend 4 to 8 SMTP mailboxes per domain as a default, and up to 50 mailboxes on a single domain is a supported, tested configuration — we've tested that density extensively and it performs the same as a lower-density setup. So the 4–8 default is about spreading risk across more domains (a domain-level problem then takes fewer mailboxes down at once), not a limit your placement depends on. See Setting up domains and mailboxes. Whatever density you choose, keep the per-mailbox numbers above — that's what your reputation actually responds to.
Your sequencer's own defaults
Some sequencers show their own generic default sending-volume settings (for example, a template value like 50/day) the first time you connect a mailbox. That default comes from the sequencer, not from Maildoso — use the numbers above instead, and update the sequencer's settings to match them.
Sticking to these numbers is also the single biggest thing you can do to keep your reputation healthy — sudden spikes above them are what damages a mailbox. See Understanding your mailbox reputation scores (Google Score & Microsoft Score) and How warmup works and how to start it.