Warmerly
5 on Starter, 25 on Growth, 100 on Agency; more on a call.
Warmerly
Apollo.io
One-to-one · Mailboxes
Mailboxes
One row, in depth: what each tool does, the verified numbers, and who each suits.
Apollo details read from its pricing page and FAQ, product pages and help centre on 21 October 2026.
Warmerly
5 on Starter, 25 on Growth, 100 on Agency; more on a call.
Apollo.io
Free and Basic: 1 per user. Professional: Google and Microsoft mailboxes not limited per user, plus 5 SMTP. Organization: plus 15 SMTP.
The short answer
Mailboxes, in one look.
Warmerly counts mailboxes: 1 on Free, 5 on Starter, 25 on Growth and 100 on Agency, with more on a call. Apollo counts mailboxes per user. Free and Basic allow 1 per user. Professional lists Google and Microsoft mailboxes as Unlimited per user, plus 5 SMTP mailboxes, and Organization adds 15. At the top end Apollo states no cap and Warmerly does. Apollo also caps daily email sends at 250 on Free and Basic, which Warmerly does not do on paid plans. Last checked 22 October 2026.
Apollo.ioApollo.io ahead on this row
Free and Basic: 1 per user. Professional: Google and Microsoft mailboxes not limited per user, plus 5 SMTP. Organization: plus 15 SMTP.
The picture
Drawn side by side.
On screen
What it looks like.
WarmerlySample data
How Warmerly does it
Warmerly, in detail.
A mailbox limit per plan, shared by the whole workspace, with warmup on every one.
01
Limits by plan
Mailboxes: 1 on Free, 5 on Starter, 25 on Growth and 100 on Agency. They are a live count: disconnect one and the slot is free at once.
Warmerly product, checked 21 October 2026
02
More than 100 on a call
Beyond Agency the Max plan is custom and is arranged on a call.
Warmerly product, checked 21 October 2026
03
Any provider
Gmail, Outlook, Zoho, Namecheap or any SMTP and IMAP mailbox can be connected, with Google and Microsoft sign-in. SMTP and IMAP hosts that point at private or internal addresses are refused.
Warmerly product, checked 21 October 2026
04
Warmup on all of them
Every connected mailbox follows the warmup ramp. Warmup sends are not metered on paid plans. Provider ceilings on warmup volume are 40 a day for Gmail, 30 for Outlook and 25 for Zoho.
Warmerly product, checked 21 October 2026
05
Hosted mailboxes sit outside the count
Hosted mailboxes bought from Warmerly do not use a plan mailbox slot, so a Starter workspace can hold its 5 connected mailboxes and add hosted ones.
Warmerly product, checked 21 October 2026
06
Hosted mailbox price by tier
A hosted mailbox is $2.99 a month on Free and Starter, $1.99 on Growth and $0.99 on Agency. There is no billing minimum on any tier, and annual billing is 10 times monthly.
Warmerly product, checked 21 October 2026
07
A free starter mailbox
Every new account gets one free mailbox on a Warmerly-owned domain, already warming up, that does not use a plan slot. After 14 days of warmup it can send a small first campaign of up to 3 emails a day to verified addresses.
Warmerly product, checked 21 October 2026
08
Daily limit per mailbox
Each mailbox has its own daily campaign limit, 30 by default, and a minimum wait between sends of 10 minutes. Five mailboxes at 30 a day is roughly 150 sends a day.
Warmerly product, checked 21 October 2026
How Apollo.io does it
Apollo.io, in detail.
Apollo limits mailboxes per user, and the limit changes by plan.
01
Free and Basic: 1 per user
The pricing page's Mailboxes per User row says 1 mailbox per user on Free and on Basic.
apollo.io/pricing · read 22 October 2026
02
Professional: Unlimited, plus SMTP
Professional lists "Unlimited Google and Microsoft mailboxes + 5 SMTP mailboxes per user". The FAQ says features labelled Unlimited have no set limit in the plan but may still be subject to a Fair Use Policy.
apollo.io/pricing · read 22 October 2026
03
Organization: Unlimited, plus more SMTP
Organization lists "Unlimited Google and Microsoft mailboxes + 15 SMTP mailboxes per user".
apollo.io/pricing · read 22 October 2026
04
Daily sends are capped on the lower plans
The Daily Emails Sends row says 250 emails on Free and Basic, and Unlimited on Professional and Organization.
apollo.io/pricing · read 22 October 2026
05
Free plan connects Gmail only
The FAQ says that on free plans you can connect Gmail accounts only. Paid plans connect Microsoft Office or any other provider. The comparison table's Email Integration row lists Gmail and Microsoft for the first plan and All Email Providers for the other three.
apollo.io/pricing · read 22 October 2026
06
Buying mailboxes starts at Basic
Domain and Mailbox Purchasing, and Deliverability Suite and Email Warmup, are listed on the Basic, Professional and Organization cards and not on Free. The FAQ says credits give access to email warmup and to domains and mailboxes.
apollo.io/pricing · read 22 October 2026
07
Bought mailboxes have a plan allowance
The help article on buying mailboxes says the number of domains and mailboxes you can purchase depends on your plan, with the credit cost shown at checkout.
knowledge.apollo.io/hc/en-us/articles/33476090833549-Generate-a-Domain-and-Mailbox-to-Reach-Prospects · read 21 October 2026
08
Scale by adding mailboxes
The sending limits article advises linking more mailboxes rather than raising the limit on one, and says the number you can connect depends on your plan.
knowledge.apollo.io/hc/en-us/articles/4409233349005-Configure-Email-Sending-Limits · read 21 October 2026
What Apollo.io does not say
We looked, and found no statement on these. That is about its published pages only, not about the product.
- A number for the mailboxes allowed on Free beyond 1 per user, or what "Unlimited" means in practice beyond the Fair Use Policy wording in the FAQ
- The credit cost of a domain or a mailbox, which the help article says is shown at checkout
- Apollo's knowledge base articles, which returned an access error when we tried to read them again on 2026-10-22, so their facts carry the read date of 2026-10-21
Where the sources disagree
We report each version rather than pick one.
- Apollo's FAQ says free plans connect Gmail accounts only, while the comparison table lists Gmail and Microsoft against the Free plan. We report both and do not say which applies.
The numbers
Only what we could verify.
| Measure | Warmerly | Apollo.io |
|---|---|---|
| Mailboxes | 5 on Starter, 25 on Growth, 100 on Agency; more on a call. | Free and Basic: 1 per user. Professional: Google and Microsoft mailboxes not limited per user, plus 5 SMTP. Organization: plus 15 SMTP. |
| Mailboxes on Free | 1 | 1 per user |
| Mailboxes on the entry paid plan | 5 | 1 per user |
| Mailboxes on Growth | 25 | No such plan |
| Mailboxes on the top published plan | 100 | Unlimited Google and Microsoft, plus 5 or 15 SMTP |
| Daily send cap on the entry paid plan | None on the plan, 30 per mailbox a day by default | 250 emails |
| Who counts the mailboxes | The workspace | Each user |
| Free plan email providers | Not restricted by provider in the docs | Gmail only, per the FAQ |
| Hosted mailbox price | $2.99, $1.99 or $0.99 a month by tier | Paid in credits, price not shown |
| Buying a mailbox on Free | Yes, a hosted one | Not listed on Free |
The plans
Every plan, side by side.
Warmerly
Free$01 mailbox · 100 campaign sends a month · no card
Starter$195 mailboxes · no cap on sends
Growth$4925 mailboxes · no cap on sends
Agency$179100 mailboxes · client workspaces · API
LinkedIn add-on$19Per connected LinkedIn account, no trial
Apollo.io
Free$01 mailbox per user · 250 emails a day
Basic$49Per seat a month, annual billing · $65 monthly
Professional$79Per seat a month, annual billing · $99 monthly
Organization$119Per seat a month, annual billing · minimum 3 seats
Per month. Apollo prices are per seat and were read on apollo.io/pricing, in its annual and monthly views, on 21 October 2026; Warmerly's email plans cover mailboxes, not people. Prices exclude tax.
In practice
What it means for you.
Our reading of the facts above. Not a promise, and not the only reasonable reading.
Several mailboxes per person
A sender who wants 3 mailboxes needs Apollo Professional at $79 a seat on annual billing. On Warmerly Starter the same 3 fit inside one $19 plan, shared with the rest of the team.
Big senders
If you want hundreds of mailboxes, Apollo lists no cap on Google and Microsoft mailboxes from Professional. Warmerly publishes prices to 100 and arranges more on a call.
A team of five, five mailboxes each
Five people each wanting 5 mailboxes is 25 mailboxes. That is one Warmerly Growth plan at $49 a month. On Apollo it is 5 Professional seats at $79, which is $395 a month on annual billing (5 times 79).
What 250 a day means
Apollo's cap of 250 emails a day, over 22 working days, is 5,500 a month (250 times 22). Warmerly's default of 30 a day per mailbox over 22 days is 660 a mailbox, so 5 mailboxes reach 3,300, and you can raise the per-mailbox limit. We could not read whether Apollo's 250 applies per user or per account.
Adding hosted mailboxes
On Warmerly Starter, 5 connected mailboxes plus 10 hosted ones at $2.99 is $19 plus $29.90, or $48.90 a month, for 15 mailboxes. The hosted ones do not use a plan slot.
Who it suits
Pick the one that fits.
Warmerly
Warmerly is the better fit if
- You want 5 or more warmed mailboxes for one low price
- Several people share mailboxes under one workspace
- You want hosted mailboxes priced per unit from $0.99 to $2.99 a month
Apollo.io
Apollo.io is the better fit if
- You want Unlimited Google and Microsoft mailboxes per user, with no number stated
- Each rep needs a seat and a mailbox of their own anyway
- You want to buy domains and mailboxes inside the same tool as your contact data
Questions
How many mailboxes does an Apollo seat include?
1 per user on Free and Basic. Professional lists Google and Microsoft mailboxes as Unlimited per user, plus 5 SMTP mailboxes, and Organization adds 15 SMTP.
How many mailboxes does Warmerly Starter include?
5, for the whole plan, with warmup on all of them.
Can I connect an Outlook mailbox on Apollo Free?
The sources disagree. The FAQ says free plans connect Gmail only, and the comparison table lists Gmail and Microsoft for the first plan. Warmerly's Free plan allows 1 mailbox, and the docs name no provider restriction.
Can I buy mailboxes through either tool?
Yes. Warmerly hosts mailboxes at $2.99, $1.99 or $0.99 a month by tier. Apollo lists Domain and Mailbox Purchasing from Basic, paid in credits.
Do hosted mailboxes use up my plan's mailbox count?
Not on Warmerly: hosted mailboxes sit outside the plan count. On Apollo we could not read how bought mailboxes count against a plan, only that the number you can buy depends on it.
Sources
- Apollo pricing page, rendered in a browser, plus its FAQ
- Apollo help: Generate a Domain and Mailbox
- Apollo help: Configure Email Sending Limits
- Warmerly plans and limits (product docs)
- Warmerly: how warmup works (product docs)
Apollo.io pages were read on 21 October 2026. Plans and wording change, so check the vendor's own page before you decide. Warmerly details come from the product as it runs today.
More features
See it on your own mailbox.
Connect a mailbox. Warmerly runs alongside whatever you send from now, so you can compare before you move anything.
Free plan, no card. Paid plans: 7-day trial, first charge on day 8.