Inframail
Flat-rate SMTP infrastructure on Microsoft-backed dedicated IPs offering unlimited mailboxes per monthly plan — cost-effective for high-inbox-count agencies but requires external warmup tools and is limited to Microsoft servers with no Google Workspace option.
Pricing breakdown
Capacity-based pricing
Pricing notes
~$79.20/mo annual, unlimited inboxes
Replacements
IP replacement available via support; 2-week warmup required after swap. Domains retained by customer after cancellation.
Our take on Inframail
Inframail's appeal is the math: a flat $129/month Unlimited plan with dedicated IPs means the more inboxes you run, the lower your effective per-mailbox cost (under $3 at 50 inboxes, and falling from there). Infrastructure spins up in about three minutes, the API is available to all subscribers, and for a Microsoft-focused operation it's one of the cheapest ways to scale.
The constraints are clear. Warmup isn't included on monthly plans (only in the done-for-you package), so dedicated IPs start cold and need a couple of weeks before volume sending. Despite the Microsoft branding, you get SMTP/IMAP credentials rather than native M365 mailboxes — and there's no Google Workspace option at all. Pricing is also in flux: the Agency Pack is moving to $327/month from July 2026, and at least one competitor has questioned how the advertised 40–50 sends/day are achieved on standard Microsoft infrastructure.
What we like
- +Flat $129/mo unlimited-inbox model — very cheap at scale
- +Dedicated IPs per account
- +API included on all plans
- +Fast infrastructure provisioning (~3 min)
Watch out for
- −No included warmup on monthly plans — IPs start cold
- −Delivers SMTP/IMAP credentials, not native M365 mailboxes
- −Microsoft-only — no Google Workspace option
- −Agency Pack price rising to $327/mo from July 2026
Best for: Microsoft-centric agencies running large inbox counts who want one flat bill and will warm up with their own tools.