How this page was made. Every price and claim below was read from each vendor's own pages on 19 September 2026 and is linked to its source; where a vendor does not publish a figure we say so. emailcampaign.ai is one of the alternatives listed and we say where it fits and where it does not. Prices change; check the linked pages before buying.
Warmbox warms one, three or six inboxes for $19, $79 or $159 a month, on more providers than most (Yahoo, iCloud, Zoho and any SMTP included). The bundles are the problem: a fourth inbox means the $159 tier, a seventh means a custom quote, and there is no free trial to check placement before paying.
Why people look for a Warmbox alternative
- Hard inbox caps per tier: one, three or six; growing past them jumps the price (source)
- No free trial, and no listing on G2 or Capterra to read before buying (source)
- Product Hunt reviewers report mail still landing in spam after warm-up, which usually means list or authentication problems warm-up cannot fix (source)
- No placement test to prove where a message lands (source)
The alternatives at a glance
| Tool | Starting price | Provisions mailboxes and domains | Warm-up | White-label |
|---|---|---|---|---|
| Warmbox | $19 a month ($15 annual) for one inbox and 50 emails a day; $79 for three; $159 for six | No | Is the product: a network described as 35,000 private inboxes, Growth, Flat and Random modes, most providers and any SMTP | None; multi-account for agencies |
| MailReach | $19.50 to $25 a mailbox a month (the page and MailReach's own blog differ) | No | Is the product: a network described as 30,000 real inboxes, up to 100 warm-up emails a day, Google, Microsoft 365 and transactional providers | None; an agency dashboard with tags |
| Warmforge | $10 a mailbox a month billed quarterly standalone; one free slot; unlimited with a Salesforge plan | No | Is the product | None (not included in the Salesforge reseller programme) |
| lemwarm | $24 a month annual ($29 monthly) per email for Essential; $40 ($49) for Smart | No | Is the product: a network described as 20,000-plus healthy domains | None |
| Saleshandy | $34 a month annual ($41 monthly) for 2,000 prospects and 6,000 emails | Yes: Google Workspace, Microsoft 365 and Azure mailboxes, pre-set with SPF, DKIM, DMARC and a tracking domain | Included through its partner TrulyInbox | Scale plan and above ($149 a month annual): custom domain and logos |
| Instantly | $37.60 a month annual ($47 monthly) for 5,000 emails and 1,000 contacts | Yes, Google only: pre-warmed accounts with DNS pre-configured; Instantly retains domain ownership and administrator access | Included, unlimited | Hypergrowth ($77.60) and Light Speed plans: custom domain and logo for a client portal; clients with campaign access see every campaign in the workspace |
| emailcampaign.ai | Free 14-day trial; Basic $39 a month; Pro $94 a month | Yes: domains (about $12 a year), Google Workspace seats ($8.40 a month), Microsoft 365 seats at Microsoft's rate, or self-hosted servers from $39 a month; you own the domains and accounts | Included, unlimited, with a maintenance level after the ramp; never reaches your inbox | Yes: a complete webmail and admin console on the client's own domain, plus dashboard branding |
1. MailReach · A warm-up and spam-test tool priced per mailbox.
| Price | $19.50 to $25 a mailbox a month (the page and MailReach's own blog differ) |
| Model | Per mailbox; spam-test credits in packs; agency pricing on request |
| Provisioning | No |
| DNS | Checks only (SPF, DKIM, DMARC, blacklists) |
| Warm-up | Is the product: a network described as 30,000 real inboxes, up to 100 warm-up emails a day, Google, Microsoft 365 and transactional providers |
| White-label | None; an agency dashboard with tags |
| Placement test | Yes, 30-plus seed mailboxes, three free tests a day |
| Reviews | G2 4.7 from about 34 to 41; Capterra 5.0 from 24 |
Best for: Teams that keep their sequencer and only want warm-up and spam tests
Watch out for: Per-mailbox cost adds up on a fleet, no native Instantly or Smartlead integration, and a Trustpilot review reports a cancelled subscription reactivating
2. Warmforge · The Salesforge group's warm-up, free inside Salesforge and paid standalone.
| Price | $10 a mailbox a month billed quarterly standalone; one free slot; unlimited with a Salesforge plan |
| Model | Per mailbox standalone; placement tests $39 a month for 100 tests or $169 unlimited |
| Provisioning | No |
| DNS | Checks |
| Warm-up | Is the product |
| White-label | None (not included in the Salesforge reseller programme) |
| Placement test | Yes, paid tiers |
| Reviews | Reviewed under the Salesforge seller aggregate on G2 |
Best for: Salesforge users, or anyone wanting warm-up plus placement tests from one vendor
Watch out for: Standalone it is priced per mailbox like MailReach; the network size is not published
Sources: Pricing
3. lemwarm · lemlist's warm-up, included with lemlist and sold standalone.
| Price | $24 a month annual ($29 monthly) per email for Essential; $40 ($49) for Smart |
| Model | Per email address; included in every lemlist plan |
| Provisioning | No |
| DNS | Deliverability setup checks |
| Warm-up | Is the product: a network described as 20,000-plus healthy domains |
| White-label | None |
| Placement test | None found |
| Reviews | Reviewed under lemlist (G2 4.6 from 1,424) |
Best for: lemlist users; otherwise an expensive per-address warm-up
Watch out for: Priced per email address, so a fleet of 30 mailboxes costs more than most outreach plans that include warm-up
Sources: lemwarm pricing
4. Saleshandy · Outreach software with unusually cheap provider mailboxes attached.
| Price | $34 a month annual ($41 monthly) for 2,000 prospects and 6,000 emails |
| Model | Plan by prospects and emails; unlimited email accounts and warm-up mailboxes; infrastructure add-on at $2.99 to $3.99 a mailbox a month plus $14 a year per domain |
| Provisioning | Yes: Google Workspace, Microsoft 365 and Azure mailboxes, pre-set with SPF, DKIM, DMARC and a tracking domain |
| DNS | Included with provisioned mailboxes |
| Warm-up | Included through its partner TrulyInbox |
| White-label | Scale plan and above ($149 a month annual): custom domain and logos |
| Placement test | None found |
| Reviews | G2 4.6 from 773; Capterra 4.5 from 126 |
Best for: Price-sensitive teams that want sequencing and mailboxes from one vendor
Watch out for: Reviews mention charges after cancellation, marketing about daily caps, and bugs after releases
Sources: Pricing · Infrastructure
5. Instantly · The most-reviewed cold email tool, with pre-warmed Google accounts as an add-on.
| Price | $37.60 a month annual ($47 monthly) for 5,000 emails and 1,000 contacts |
| Model | Plan by emails and contacts; unlimited email accounts and warm-up; pre-warmed Google accounts $10 each a month in batches of five, domains $15 a year |
| Provisioning | Yes, Google only: pre-warmed accounts with DNS pre-configured; Instantly retains domain ownership and administrator access |
| DNS | Pre-configured on provisioned accounts |
| Warm-up | Included, unlimited |
| White-label | Hypergrowth ($77.60) and Light Speed plans: custom domain and logo for a client portal; clients with campaign access see every campaign in the workspace |
| Placement test | Yes, a separate Inbox Placement product with 25 free credits |
| Reviews | G2 4.8 from 4,134; Trustpilot score withheld, 1,165 reviews with 25 percent one-star |
Best for: Teams that already own their mailboxes and want the largest community and template library
Watch out for: Provisioned domains stay owned by Instantly; reviews report features behind paywalls that only appear after purchase and pre-warmed domains arriving with poor reputation
Sources: Pricing · Pre-warmed accounts · White-label
6. emailcampaign.ai · Cold email software that provisions and warms its own infrastructure, with a white-label door for agencies.
| Price | Free 14-day trial; Basic $39 a month; Pro $94 a month |
| Model | Plan by emails per month; unlimited mailboxes and warm-up on every plan; infrastructure at cost plus $5 setup per mailbox |
| Provisioning | Yes: domains (about $12 a year), Google Workspace seats ($8.40 a month), Microsoft 365 seats at Microsoft's rate, or self-hosted servers from $39 a month; you own the domains and accounts |
| DNS | SPF, DKIM (selectors read from the provider), DMARC and postmaster records written through the registrar and shown before they go live |
| Warm-up | Included, unlimited, with a maintenance level after the ramp; never reaches your inbox |
| White-label | Yes: a complete webmail and admin console on the client's own domain, plus dashboard branding |
| Placement test | Yes, per mailbox at Gmail and Outlook |
| Reviews | New listing; reviews being gathered |
Best for: Teams that want the mailboxes, domains, DNS and warm-up done for them behind one approval, and agencies that need a client-branded door
Watch out for: The recommended 8 to 10 sends a day per mailbox means volume comes from fleet size; if you want 100 a day from one mailbox, nothing here will let you
Sources: Pricing · Infrastructure
How to choose
- Decide who owns the domains and accounts. Some vendors keep ownership or administrator access; if you may leave, you want yours in your own name.
- Count the year-two price, not the launch price. Several infrastructure vendors step prices up after twelve months or sell pre-warmed mailboxes that expire.
- Ask what happens when a domain burns. Replacement policy, and whether the vendor pauses the sender or quietly suppresses your recipients.
- Check the review sites for cancellation stories. They are the most consistent complaint in this category across vendors.
- Send at 8 to 10 a day per mailbox whatever you buy. No vendor's mailbox survives 100 a day to strangers.
Questions, answered straight
- What is the cheapest way to warm ten mailboxes?
- Inside an outreach plan that includes unlimited warm-up: Saleshandy from $34 a month, Smartlead from $32.50, Instantly from $37.60, or emailcampaign.ai from the free trial. Standalone per-mailbox tools cost $10 to $25 a mailbox a month.
- Does Warmbox's provider breadth matter?
- Only if you send cold email from Yahoo, iCloud or Zoho, which you should not. For Google Workspace, Microsoft 365 and your own servers every tool on this page works.
- How long should warm-up run?
- Two to three weeks to the target, then a maintenance level for the life of the mailbox. Turning warm-up off when campaigns start is the most common self-inflicted deliverability problem we see.
Published 19 September 2026. Updated 19 September 2026. Written by the team that runs the infrastructure; numbers come from the platform's own provisioning and sending, and from the providers' published documentation at the time of writing.