Winnr
Privately operated SMTP infrastructure for high-volume cold email, emphasizing the lowest per-mailbox cost, a full REST API (plus an MCP server), optional dedicated IPs, and a 90%-deliverability-or-refund guarantee on month-to-month billing.
Pricing breakdown
| Platform | Standard | Warmed | Volume |
|---|---|---|---|
| Dedicated SMTP | $1.38 | — | — |
Pricing notes
Monthly billing, no annual lock-in. Startup $69/mo for 50 mailboxes (~$1.38/mb); Enterprise $189/mo for 200 (~$0.95/mb); extra mailboxes $1 each. Dedicated IPs +$20/mo (Enterprise). Warmup add-on $0.60/mb/mo. No per-send fees; SPF/DKIM/DMARC auto-configured; full REST API + MCP server. Leadgen Jay reported ~$0.80/mb at scale.
Replacements
90% deliverability guarantee or full refund; no specific burned-domain replacement terms stated.
Our take on Winnr
Winnr is built around price and control. It runs its own SMTP infrastructure at roughly $0.95-1.38 per mailbox (less at volume), sets up in under ten minutes with DNS auto-configured, and is unusual in offering a full REST API plus an MCP server, which makes it appealing if you want to provision and monitor inboxes programmatically. Billing is month-to-month with no annual lock-in, and there's a 90%-deliverability-or-refund guarantee. It's also the provider Leadgen Jay said he moved to after testing six at scale, citing a cost near $0.80/mailbox.
The trade-offs are the standard private-SMTP ones. These aren't real Google Workspace or Microsoft inboxes, so deliverability leans more on your domains, warmup and copy than on a borrowed Google or Microsoft reputation. IPs are shared unless you pay for dedicated, and warmup is a separate add-on rather than included. The company is still relatively young with a modest review count, so as with any SMTP provider, test inbox placement on a small batch before committing a large fleet.
What we like
- +Among the cheapest SMTP options (~$0.95-1.38/mailbox, lower at scale)
- +Full REST API plus an MCP server for programmatic control
- +Fast setup (under 10 min) with SPF/DKIM/DMARC auto-configured
- +Month-to-month billing, no annual lock-in; 90% deliverability-or-refund guarantee
Watch out for
- −Shared IPs by default; dedicated is a paid add-on
- −Warmup is a separate paid add-on, not included
- −Private SMTP, not real Google/Microsoft inboxes, so placement rides on your setup
- −Relatively young, with a modest ~19 Trustpilot reviews
Best for: High-volume senders and agencies chasing the lowest SMTP cost who want API control and month-to-month billing, and who'll run their own warmup.