Cheapest SMTP inboxes for cold email (October 2026)
SMTP mailboxes aren't hosted on Google or Microsoft. They're the cheapest way to add sending volume, and they come in shared-IP and private/dedicated-server flavours. For 30 inboxes on 10 domains, USD-priced SMTP options run $79.83 to $257.72/mo. Cheapest: Winnr at $79.83/mo; EU-hosted Outboxes lists €49/mo (excl. VAT).
Last updated 2026-10-23 · 8 offerings · list prices, monthly billing
Verdict by use case
Price comparison
| Platform | + 10 domains | Minimum | Warmup | Link | ||||
|---|---|---|---|---|---|---|---|---|
Outboxes EU-hosted private SMTP mailboxes |
SMTP | €0.78 | €39 | €10.00 | €49 | 5 domains (EUR 19.50/month) | No | View pricing |
| SMTP | $1.38 | $69 | $10.83 | $79.83 | Startup plan ($69/month) | Add-on | View pricing | |
Maildoso SMTP mailboxes (15 sends/day cap) |
SMTP | $2.50 | $75 | $12.50 | $87.50 | 30 mailboxes | No | View pricing |
Mailpool SMTP inboxes |
SMTP | $3.00 | $90 | $8.72 * | $98.72 | None stated | Unknown | View pricing |
Mailforge Shared-IP SMTP mailboxes |
SMTP | $3.00 | $90 | $11.67 | $101.67 | 10 mailbox slots | No | View pricing |
Infraforge Private SMTP, dedicated servers |
SMTP | $4.00 | $120 | $11.67 | $131.67 | 10 mailbox slots; quarterly or yearly billing | No | View pricing |
Mission Inbox Dedicated-IP outbound mailboxes |
SMTP | $3.33 | $199 | $8.72 * | $207.72 | 15 mailboxes (Lite) | Unknown | View pricing |
Mailreef Dedicated mail server |
SMTP | Server plan | $249 | $8.72 * | $257.72 | One server | Optional | View pricing |
Total = list price for 30 mailboxes on the cheapest plan that fits + 10 sending domains amortised monthly. * Domain price unknown or bring-your-own: reference .com at $10.46/yr. † Price from a third-party comparison. € rows are in euros excl. VAT and are excluded from "cheapest" badges. Monthly billing, list prices, checked 2026-10-23.
Frequently asked questions
What is the cheapest SMTP inbox provider for cold email?
Winnr at $79.83/mo for 30 mailboxes incl. domains (USD-priced). Lowest per-mailbox price: $1.38 (Winnr).
Shared vs private SMTP: what's the difference?
Shared SMTP puts many customers on the same sending IPs, which is cheaper. Private SMTP gives you dedicated servers or IPs at a higher price. Both types are in the table.
Do SMTP inboxes have sending caps?
Some do. In our data: Maildoso (15 cold emails per mailbox per day); Mission Inbox (10,000 sends/month on the Scale plan (warmup counts)).