Warmerly
100 on Agency ($179); more on a call
Warmerly
Smartlead
One-to-one · Most mailboxes on a published price
Most mailboxes on a published price
One row, in depth: what each tool does, the verified numbers, and who each suits.
Smartlead details read from its pricing page, home page and help centre on 17 and 19 October 2026.
Warmerly
100 on Agency ($179); more on a call
Smartlead
No limit on any plan
The short answer
Most mailboxes on a published price, in one look.
Warmerly's top published plan, Agency at $179 a month, connects 100 mailboxes. Anything above that is Max, priced on a call. Smartlead's plan pages say all plans include unlimited email accounts, so they show no ceiling. Its Fair Use Policy applies on unlimited plans and lists 100, 300 and 800 mailboxes against plan names that do not all match today's, without saying how they apply. Last checked 19 October 2026.
SmartleadSmartlead ahead on this row
No limit on any plan
The picture
Drawn side by side.
Where each ceiling sits on the fleet ruler
Fleet size on a log axis, 1 to 1,000 mailboxes. Warmerly stops at 100 on a published price. Smartlead's plan pages show no ceiling.
WarmerlySmartlead
Warmerly
Growth
Up to 25 mailboxes, $49 a month.
Smartlead
No ceiling stated
The numbers behind this chart
| Who | Mailboxes |
|---|---|
| Warmerly Starter | Up to 5 mailboxes |
| Warmerly Growth | Up to 25 mailboxes |
| Warmerly Agency | Up to 100 mailboxes |
| Warmerly Max | More than 100 mailboxes, priced on a call |
| Smartlead, every plan | Unlimited email accounts on its plan pages, no ceiling stated |
| Smartlead accounts, smallest quarter | 7 mailboxes or fewer |
| Smartlead accounts, median | 20 mailboxes |
| Smartlead accounts, largest quarter | 60 mailboxes or more |
| Smartlead fair use policy | 100 (Basic plan), 300 (Popular plan) and 800 (Pro plan) mailboxes, plan names that do not all match today's, not explained |
Warmerly prices: Starter $19, Growth $49, Agency $179 a month. Max has no published price. Smartlead benchmark data covers senders with at least 500 emails sent, January to June 2026, and comes from Smartlead's own platform. The fair use policy is undated.
How many mailboxes would a plan's emails take?
Mailboxes needed to send each Smartlead plan's monthly emails, if every mailbox sends the same amount each day.
WarmerlySmartlead
Warmerly Agency, $179 a month
Connects up to 100 mailboxes on a published price. Above that is Max, priced on a call.
- Base7fits Agency
- Pro100fits Agency
- Unlimited Smart167needs Max
- Unlimited Prime556needs Max
The numbers behind this chart
| Smartlead plan | Emails a month | Mailboxes at 30 a day | Mailboxes at 50 a day | Within Warmerly's published 100? |
|---|---|---|---|---|
| Base | 6,000 | 7 | 4 | Yes at 30; yes at 50 |
| Pro | 90,000 | 100 | 60 | Yes at 30; yes at 50 |
| Unlimited Smart | 150,000 | 167 | 100 | No, needs Max at 30; yes at 50 |
| Unlimited Prime | 500,000 | 556 | 334 | No, needs Max at 30; no at 50 |
At 30 a day over 30 days, Warmerly's 5 Starter mailboxes top out near 4,500 sends a month, 25 on Growth near 22,500 and 100 on Agency near 90,000. Smartlead's benchmark page gives 50 as its per-mailbox ceiling and 14 a day as the median pace.
How Warmerly does it
Warmerly, in detail.
100 mailboxes on Agency at $179 a month is the most Warmerly publishes. Past it, Max is agreed on a call.
01
Agency is 100
Agency allows 100 mailboxes. The code comment says it was set to 100 so the price per mailbox keeps falling as plans grow ($1.79 on Agency).
Warmerly product, checked 19 October 2026
02
Agency also gets client workspaces
Agency has client workspaces that share one pool of 100 mailboxes, with separate campaigns and replies per client, and API access.
Warmerly product, checked 19 October 2026
03
Beyond 100
Max is for more than 100 mailboxes. It has no published price or mailbox figure and is set up through a call, so we do not state either.
Warmerly product, checked 19 October 2026
04
Hosted mailboxes sit outside the slot count
Hosted mailboxes bought from Warmerly do not use a plan slot, and cost $0.99 a month each on Agency.
Warmerly product, checked 19 October 2026
05
Sending per mailbox
Each mailbox has a daily campaign limit, 30 by default. 100 mailboxes at 30 a day is 3,000 a day, about 90,000 a month (our arithmetic, before the ramp and reputation brake). The same arithmetic gives near 4,500 a month for 5 mailboxes and near 22,500 for 25.
Warmerly product, checked 19 October 2026
06
Price per mailbox falls to the top
$3.80 on Starter, $1.96 on Growth and $1.79 on Agency (price divided by mailboxes, our arithmetic). Agency was set at 100 so the curve keeps falling.
Warmerly product, checked 19 October 2026
07
Agency's other limits
Agency has no cap on active campaigns, 250,000 active prospects and 100,000 leads per campaign.
Warmerly product, checked 19 October 2026
08
The ceiling is enforced when you connect
Connecting past the limit is refused at that moment, with a message, rather than showing up on a later bill.
Warmerly product, checked 19 October 2026
How Smartlead does it
Smartlead, in detail.
No ceiling on its plan pages: unlimited email accounts on every plan, with emails and contacts metered. Its fair use policy applies on top and names 100, 300 and 800 mailboxes against plan names (Basic, Popular, Pro).
01
Unlimited accounts on every plan
The pricing FAQ says all plans include unlimited email accounts at no extra cost, so the most mailboxes on a published price is not capped.
smartlead.ai/pricing · read 19 October 2026
02
Large fleets are normal there
Its benchmark page says the biggest quarter of accounts run 60 or more mailboxes. A customer quote on the home page claims 7,767+ inboxes managed; that is a customer claim, not a Smartlead figure.
smartlead.ai/benchmarks/how-many-mailboxes-for-cold-email and https://www.smartlead.ai · read 19 October 2026
03
Volume tops out at 500,000 emails
The highest published plan, Unlimited Prime at $379, lists 500,000 emails a month. Smartlead's managed SmartServices list 50,000 and 100,000 email tiers with no price.
smartlead.ai/pricing · read 19 October 2026
04
Clients and white-label
The FAQ says adding clients is available from Pro, Unlimited Prime includes 3 client workspaces, and white-labelling is $29 a month per client workspace.
smartlead.ai/pricing · read 19 October 2026
05
Dedicated servers
SmartServers are listed at $39 per server a month, with 3 included on Unlimited Prime.
smartlead.ai/pricing · read 19 October 2026
06
Its own sizing for big fleets
Its blog says 1,000 emails a day takes 20 to 30 mailboxes, 5,000 a day takes 100 to 150 and 10,000 a day takes 200 plus. It describes the plans as having no tier-based cap and no per-mailbox fee.
smartlead.ai/blog/unlimited-mailboxes-cold-email · read 19 October 2026
07
Daily limits are shared across campaigns
The help centre says a sender account's daily limit is split across the campaigns it is in, and it resets at 00:00 in the account's timezone.
helpcenter.smartlead.ai/en/articles/228-my-campaign-is-not-sending-emails-or-sending-less-volume · read 19 October 2026
08
What Prime adds at the top
Unlimited Prime lists 500,000 emails a month, unlimited contact storage (help centre), 3 client workspaces, private infrastructure, a dedicated account manager and a private Slack channel.
helpcenter.smartlead.ai/en/articles/439-smartlead-pricing-plans · read 19 October 2026
09
The smallest accounts
Its benchmark page says the smallest quarter of accounts run 7 mailboxes or fewer, and the data covers senders with at least 500 emails sent, January to June 2026.
smartlead.ai/benchmarks/how-many-mailboxes-for-cold-email · read 19 October 2026
10
The fair use policy names mailbox figures
Section 4 of its Fair Use Policy says fair and reasonable use applies even on unlimited plans, then lists 'Basic plan - 100 mailboxes; Popular plan - 300 mailboxes and Pro plan - 800 mailboxes' under unreasonable use. Only Pro matches a current plan name (today's are Base, Pro, Unlimited Smart and Unlimited Prime), and the page does not say whether these are caps or how they map to Base, Pro, Smart and Prime.
smartlead.ai/fair-use-policy · read 19 October 2026
What Smartlead does not say
We looked, and found no statement on these. That is about its published pages only, not about the product.
- What a very large fleet costs in practice: depends on emails and on any SmartSenders or SmartServers spend, which the page does not total.
- How the benchmark's 50 a day per mailbox ceiling was set: not explained on the page.
- A documented maximum of connected accounts per workspace on its plan pages, fact sheet or help articles: none stated.
- How the fair use policy's 100, 300 and 800 mailbox figures map to today's plans, or whether they are enforced limits: not stated.
The numbers
Only what we could verify.
| Measure | Warmerly | Smartlead |
|---|---|---|
| Most mailboxes on a published price | 100 on Agency ($179); more on a call | No limit on any plan |
| Most mailboxes on a published plan | 100 (Agency) | No limit stated on its plan pages |
| Price of that plan | $179 a month | $39 a month (Base) already lists unlimited accounts |
| Above the top published plan | Max, priced on a call | No ceiling on its plan pages; fair use policy lists 100, 300 and 800 mailboxes against plan names that do not all match today's (Basic, Popular, Pro) |
| Cost per mailbox at the top | $1.79 ($179 / 100, our arithmetic) | Depends on emails and add-ons |
| Client workspaces | Agency, sharing one pool of 100 mailboxes | From Pro; 3 on Prime; white-label $29 per client a month |
| Highest published send volume | No meter; about 90,000 a month at 100 mailboxes and 30 a day (our arithmetic) | 500,000 a month (Prime, $379) |
| Median customer fleet | Not published | 20; top quarter 60 or more (its benchmark page) |
| What the top published fleet can send in a month | About 90,000 (100 mailboxes, 30 a day, 30 days; our arithmetic) | Pro lists 90,000 emails a month for $94 |
| Smallest quarter of accounts | Not published | 7 mailboxes or fewer (its benchmark page) |
| Daily pace per mailbox | 30 by default, set per mailbox | 14 a day median, 50 ceiling (its benchmark page) |
| Mailboxes for 5,000 emails a day | Agency's 100 at 30 a day is 3,000 a day (our arithmetic) | 100 to 150 (its blog) |
| Mailboxes needed for each Smartlead plan's emails at 30 a day | 7 for Base's 6,000, 100 for Pro's 90,000, 167 for Smart's 150,000 and 556 for Prime's 500,000 (our arithmetic; Agency stops at 100) | No mailbox cap stated on its plan pages |
| Mailbox figures in its fair use policy | Not applicable | 100, 300 and 800 mailboxes against plan names that do not all match today's (Basic, Popular, Pro), not explained |
| Mailboxes needed for each plan's emails at 50 a day (its benchmark ceiling) | 4, 60, 100 and 334 for Base, Pro, Smart and Prime (our arithmetic); Warmerly's default is 30 a day | No mailbox cap stated on its plan pages. At 50 a day, 100 mailboxes would carry Unlimited Smart's 150,000 a month (our arithmetic) |
The plans
Every plan, side by side.
Warmerly
Free$01 mailbox · capped sends · no card
Starter$195 mailboxes · no cap on sends
Growth$4925 mailboxes · no cap on sends
Agency$179100 mailboxes · client workspaces · API
Smartlead
Base$396,000 emails · 2,000 contacts
Pro$9490,000 emails · 30,000 contacts
Unlimited Smart$174150,000 emails
Unlimited Prime$379500,000 emails
Per month, billed monthly. Every Smartlead plan lists unlimited email accounts; prices read on smartlead.ai/pricing on 17 October 2026 and re-checked on 19 October 2026.
In practice
What it means for you.
Our reading of the facts above. Not a promise, and not the only reasonable reading.
This is Smartlead's strongest row
Our reading: for fleets over 100 mailboxes, Smartlead's lack of a published ceiling is simpler than a Warmerly Max call. Its fair use policy leaves some doubt, so confirm with Smartlead.
100 covers most teams
Our reading: Smartlead's own data puts the median account at 20 mailboxes and the top quarter at 60 or more, so 100 is above what most use.
Agency is built for client work
Our reading: if you run client mailboxes under 100, Agency gives separate workspaces for $179. Smartlead charges $29 a month per client for white-label on top of its plan.
Unlimited is not the whole bill
Our reading: a huge fleet on Smartlead still pays for emails sent and for any mailboxes or servers it supplies.
At the top, the email meter does the limiting on Smartlead
Our reading: with no mailbox cap, a very large fleet on Smartlead is held back by its email allowance. Prime's 500,000 a month is the most it lists, and at 30 a day that is 556 mailboxes' worth of sending.
100 mailboxes at 30 a day matches Pro's email line
Our reading: a full Agency fleet sends up to about 90,000 a month, the same size as Smartlead Pro's 90,000. The two tools reach the same sending size by different meters.
Smartlead's own data says most accounts stay small
Our reading: the smallest quarter run 7 mailboxes or fewer and the median runs 20, so the question of a ceiling matters mostly to the top quarter, at 60 or more.
Ask Smartlead before planning a very large fleet
Our reading: its plan pages show no ceiling, but its fair use policy says fair use applies to unlimited plans and mentions mailbox figures it does not explain. If you plan well past 100, get the real limit in writing from Smartlead, and do the same with Warmerly's Max call.
Who it suits
Pick the one that fits.
Warmerly
Warmerly is the better fit if
- You need up to 100 mailboxes at a flat $179 with client workspaces.
- You want a hard ceiling that stops overspend.
- You want hosted mailboxes at $0.99 each on Agency without using a slot.
- You are happy to agree a custom price if you outgrow 100.
Smartlead
Smartlead is the better fit if
- You need more than 100 mailboxes on published pricing.
- You expect your fleet to keep growing without a plan change.
- You want dedicated servers (SmartServers) and ready-made mailboxes.
- You send very high volume, up to 500,000 emails a month on a published price.
Questions
How many mailboxes can Warmerly connect?
100 on Agency at $179 a month, which is $1.79 a mailbox by our arithmetic. Above that is Max, priced on a call.
Does Smartlead cap mailboxes?
Its plan pages say all plans include unlimited email accounts. Its Fair Use Policy lists 100, 300 and 800 mailboxes against plan names that do not all match today's.
What is Smartlead's median fleet?
20 mailboxes, with the top quarter at 60 or more, per its benchmark page.
How many mailboxes do 500,000 emails a month need?
About 556 at 30 a day or 334 at 50 a day, by our arithmetic, which is beyond Warmerly Agency so a Max call.
Sources
- Smartlead pricing
- Smartlead home page
- Smartlead help: lead and email credits
- Smartlead help: do credits reset
- Smartlead benchmark: how many mailboxes
- Smartlead help: pricing plans
- Smartlead help: my campaign is not sending or sending less volume
- Smartlead help: email account disconnection reasons
- Smartlead blog: unlimited mailboxes for cold email
- Smartlead: pricing as a markdown fact sheet
- Smartlead: fair use policy
Smartlead pages were read on 19 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
- All features
- Starting price (per month)
- Mailboxes on the starting plan
- Emails per month on the starting plan
- Highest published send volume
- Contacts on the starting plan
- Warmup
- Spam-folder rescue
- SPF, DKIM and DMARC monitoring
- Inbox placement testing
- Built-in campaign sender
- Shared reply inbox
- LinkedIn steps in the same sequence
- Ready-made mailboxes
- Agency and white-label
- Integrations
- API
- Free plan or trial
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.