Guide

Best Inbox Providers for Cold Email (2026)

We tested the top inbox providers for cold email. Here are the best options based on pricing, deliverability, and infrastructure type. Read our full reviews: Hypertide, Infraforge, Mailforge. Building a full stack? See Best Cold Email Tools for Clay Users.

Our Methodology

We evaluated providers on deliverability quality, pricing, setup speed, and infrastructure type (shared vs dedicated IPs).

Hypertide

Best Overall Value

Hypertide offers 50 Azure inboxes for $50/month ($1/inbox) with tenant isolation. Real Microsoft infrastructure, automated setup, ready in 4-6 hours.

Best for: Teams needing 50+ inboxes with quality infrastructurePricing: Contact for pricing

Infraforge

Best for Dedicated IPs

Infraforge gives you dedicated IPs at $3-4/inbox/month. Full control over your sending infrastructure and isolated reputation. More setup than turnkey options, but worth it for control.

Best for: Teams who want isolated reputation and full infrastructure controlPricing: $3.33/inbox/month (yearly)

Mailforge

Best Budget Option

Mailforge is the go-to for teams who need to scale cheaply. $2-3/inbox, ready in minutes, shared IPs. Accept the tradeoffs and it works great.

Best for: Bootstrappers, testers, and high-volume budget sendersPricing: $2-3

Maildoso

Cheapest Mailboxes

Maildoso offers SMTP mailboxes at $1.80/inbox plus domains at $8/year. Shared IPs, but hard to beat on pure mailbox cost. Good for testing and scaling.

Best for: Maximum cost savings on mailboxesPricing: $1.80

Inframail

Best for Unlimited Inboxes

Inframail offers unlimited inboxes at $129-327/month flat fee with dedicated US IPs. Great value at scale - the per-inbox cost drops to nearly nothing.

Best for: Teams who need lots of inboxes without per-seat costsPricing: Flat rate for unlimited inboxes

Primeforge

Best Google/Microsoft on US IPs

Primeforge offers real Google/Microsoft inboxes on US IPs at $3.50-4.50/inbox. Part of the Forge ecosystem with Mailforge and Infraforge.

Best for: US-focused outreach with Google/Microsoft qualityPricing: Contact for pricing

ScaledMail

Best for Pre-Warmed Inboxes

ScaledMail provides pre-warmed inboxes ready to send. Skip the warmup period and start campaigns faster.

Best for: Teams who need to launch quickly without warmup delaysPricing: Contact for pricing

Honorable Mentions

Mailreef: Dedicated server + IP at $240-249/month for 150+ mailboxes
Mission Inbox: Compliance-focused for regulated industries
InboxKit: US-IP Google/Microsoft at $2.50-3.10/inbox

Conclusion

Pick a provider that fits your budget and scale.

Premium: Hypertide at $1/inbox (isolated tenants) or Infraforge for dedicated IPs.

Budget: Mailforge or Maildoso. Accept more variability.

Unlimited: Inframail's flat-fee model.

Whichever you choose, monitor inbox performance. Even premium providers have inboxes that underperform.

Already have inboxes? See which ones actually work.

Get a free deliverability audit for your Smartlead or Instantly account. Takes 15 seconds, shows you exactly which inboxes are underperforming.

No signup required. Full results, nothing gated.

Last updated: 2026-03-05