7 Best Slicey Alternatives for Cold Email in 2026

HyperTide is the closest like-for-like on Slicey's cheap-Microsoft pitch: Azure/Entra-native Outlook inboxes at roughly $0.50 to $1.00 per inbox (around $50 per order of 100 inboxes across 2 domains), with a native Outlook UI. It is the budget Microsoft specialist.

The catches: about a 5,000 emails/month cap per order, an undisclosed one-time initiation fee, and limited transparency, so model the all-in cost carefully.

ScaledMail's Outlook tier ($50/domain for 25 mailboxes, about $2 each) is a managed alternative to Slicey's density model, with a lower (more conservative) inboxes-per-domain count. You can also blend in Google and SMTP. A 2,000-emails-per-day blended setup runs roughly $398/month base.

A done-for-you alternative when you want Outlook volume without betting on 49 to 99 inboxes per domain. No self-serve dashboard, reporting is a paid add-on, and no free trial.

PrimeForge sells real Google and Microsoft mailboxes self-serve at $4.50/mailbox monthly or $3.50 annually (10-slot minimum), pre-warmed with automated DNS, US IPs, and ESP matching, with published pricing and a dashboard.

A transparent, self-serve alternative if you want both Google and Microsoft without leaning on a density bet. Higher per-mailbox price than Slicey or InboxKit's Azure, a multi-product ecosystem, and no standalone monitoring.

Zapmail offers pre-warmed Microsoft 365 (and Google) mailboxes with OAuth setup in about 10 minutes, ZapShield monitoring, and placement testing credits. Plans run $39/$99/$299 for 10/30/100 mailboxes from a $2.50/mailbox floor, with published pricing.

If you want Microsoft inboxes ready to send with monitoring and no density bet, Zapmail is the pre-warmed alternative. No Azure, API locked to the Pro tier, and placement credits capped per plan.

If Slicey's appeal was purely the lowest cost per send, Maildoso competes on SMTP: a floor as low as $0.80/mailbox at scale and a hero rate near $1.80, with combo plans that add official Google Workspace, three-day placement testing, and self-healing mailboxes.

For the lowest cost per send with self-serve transparency, Maildoso is the budget pick, with SMTP rather than Microsoft inboxes. No Microsoft 365, Google only in Combo bundles, and no managed warmup product.

Mailforge offers shared-IP mailboxes at $3/mailbox monthly or $2 annually (effective floor around $2.42 at 200+), with free automated DNS and works with any sending software positioning, all self-serve.

The cheapest transparent, self-serve alternative if you accept shared IPs and bring your own monitoring. Warmup and monitoring are separate Forge products, and these are not real Google/Microsoft accounts.