Tool profile
Warmup Inbox: cost, fit and limits
Warmup Inbox is a mailbox warmup service made by the Slovak company CyberPanda s. r. o. that connects to an existing email account and exchanges automated messages to build sending reputation. It is aimed at cold outreach teams and agencies that send from many Google or Microsoft mailboxes.
What to know first
Warmup Inbox prices per inbox, with volume discounts that fall steeply once you manage dozens of mailboxes. The three paid tiers differ in daily warmup messages and reply rate rather than in basic function, and the free tier is a trickle of 15 emails a week. The AI wording on the pricing page centers on human-like generated content, with custom templates and warmup topics on Pro. Integrations are not listed there.
Warmup Inbox at a glance
| Maker | CyberPanda s. r. o., Slovakia |
|---|---|
| Free plan | Yes |
| Entry price | $15 per inbox per month, billed annually |
| API access | Yes |
| Category | Best AI Email Deliverability Tools in 2026, rank 4 of 11 |
| Website | warmupinbox.com |
Who Warmup Inbox is best for
Agencies warming dozens of client inboxes
The price per inbox falls with volume, with Basic annual dropping to $7.50 at 50 inboxes, and the enterprise tier adds multi-client workspaces and consolidated billing from 51 inboxes.
Teams that want to test before paying
A free tier gives 15 emails a week forever, and a seven-day full-access trial on any plan is offered without a credit card, according to the pricing page FAQ.
Multilingual outreach senders
Pro adds language warmup and warmup topic selection, so the automated conversations can match the language of the market a mailbox will prospect in.
Warmup Inbox plans and pricing
| Plan | Price | What it includes |
|---|---|---|
| Freemium | $0 forever | 15 warmup emails a week. It works as a trial of the mechanism, not as a way to warm a mailbox for production use. |
| Basic | $15 per inbox a month annually, $19 monthly | 75 warmup messages a day, a reply rate up to 25 percent and human-like AI generated content. |
| Pro | $49 per inbox a month annually, $59 monthly | 250 messages a day, reply rate up to 45 percent, custom templates, topic selection and language warmup. |
| Max | $79 per inbox a month annually, $99 monthly | 1,000 messages a day, reply rate up to 50 percent, premium support, early access to features and an unlimited developer API. |
| Enterprise | Quote after a call | For 51 or more inboxes, with consolidated billing, multi-client workspaces, specialized reports, onboarding and priority support. |
Checked November 2026.
What Warmup Inbox does
- Reply-rate bands
- Each tier states a reply rate for warmup conversations, from up to 25 percent to up to 50 percent. These are the vendor's own figures, so they describe how the system behaves rather than what mailbox providers see.
- Spam and category monitoring
- The pricing page lists monitoring of where messages land and a reputation check, so a user can see whether warmup mail reaches the inbox or falls into a promotions or spam folder.
- Outreach sequences
- Alongside warmup, the page lists outreach sequences and dashboards. It does not say how deep the sequencing goes, so a team with complex campaigns should check it against a dedicated sequencer.
- Developer API
- An API is listed on the plans and described as unlimited on Max, which lets an agency script adding and removing mailboxes as client accounts change.
- Volume discounts
- Annual Basic drops from $15 to $14 at five inboxes, then $12.50, $11, $9 and $7.50 at 10, 15, 25 and 50 inboxes, with monthly rates stepping down in a similar way.
How Warmup Inbox handles your data
Warmup Inbox's privacy policy names CyberPanda s. r. o. with a registered address in Bratislava, Slovakia. It says the platform connects directly to your inbox and that the company does not scan emails or inboxes for any purpose other than generating and sending emails for registered users. Google user data follows Google's Limited Use requirements. Account data is kept while the account is active, then deleted or anonymized within 24 months of closure. The policy names no hosting location, says storage is handled by third-party providers, and allows transfers outside the EEA. It makes no statement on AI training, and certifications were not checked.
Where Warmup Inbox falls short in practice
- Pricing is per inbox. Cost scales with every mailbox, and the Pro tier at $49 a month annually is more than three times Basic. A team that wants higher daily volume pays for it on each inbox separately.
- No stated hosting region or certifications. The policy and pricing page name no hosting provider, region or security certification. A European buyer subject to a vendor risk review will need to request those documents directly.
- Warmup alone does not fix sending. Warmup builds a mailbox history, but it does not repair broken SPF or DKIM, a purchased list or high complaint rates. Those problems stay with the sender and show up as soon as real campaigns start.
Works with
Alternatives to Warmup Inbox
Warmup Inbox: common questions
How long is the Warmup Inbox free trial?
The pricing page describes a seven-day free trial with full access on a plan you choose, and its FAQ says no credit card is required up front. There is also a Freemium tier at $0 that allows 15 emails a week with no time limit.
How many inboxes do I need before discounts start?
Per-inbox discounts begin at five inboxes, where Basic annual drops from $15 to $14. Further steps appear at 10, 15, 25 and 50 inboxes, reaching $7.50. At 51 or more, pricing is set after a call with a specialist, according to the pricing page.
Does Warmup Inbox read the emails in my mailbox?
Its privacy policy says it does not scan emails or inboxes for any purpose except to generate and send emails for registered users. It also states that Google user data is subject to Google's Limited Use requirements. The policy does not describe whether message content is stored.
Can I change plans mid-month?
The pricing page says upgrades apply immediately and downgrades take effect at the next billing cycle. Inboxes added mid-month are prorated. Annual billing saves 20 percent against monthly, and payment is by Visa, Mastercard or American Express handled through Stripe.
Where is Warmup Inbox based?
The privacy policy gives the operator as CyberPanda s. r. o., with a registered address at Obchodna 2 in Bratislava, Slovakia. It does not name where data is hosted, only that third-party providers handle storage and that transfers outside the EEA can occur.