Email Warmup Pricing in 2026: What 20 Tools Charge, and What 10 Mailboxes Cost

A cold email program that sends from thirty mailboxes pays for warmup thirty times, or once, depending on which vendor it picked. No other category in the outbound stack has pricing models that diverge this much for the same job. The entry prices look alike, and the bills at real scale differ by a factor of more than a hundred.

RevenueFlow's verified vendor dataset holds pricing records for 20 dedicated email warmup tools, each read from the vendor's own pricing page between 2026-08-28 and 2026-09-04. The category is small enough to show in full, so this study prints every tool's entry plan, then answers the question the entry prices hide: what does it cost to warm ten mailboxes?

What warmup tools charge to get started

18 of the 20 tools publish a subscription price. Their median starting price is $29 a month, and half of them start between $19 and $39.75. The lowest entry price on the record is $5 and the highest is $149.

That is one of the tightest price bands of any sales tool category. It is also close to meaningless on its own, because the entry plan buys different things at different vendors: one mailbox at most, three or five at some, fifty or unlimited at a few.

Three things stand out in the full table. 11 of the 20 tools (55%) carry a quote-only tier for agencies or large mailbox counts, and 1 publishes no price at all. Only 3 list a $0 tier. And the top published tier is a long way from the entry tier: its median is $129 a month, and a quarter of tools publish a top tier of $409 or more.

Two pricing models

Reading each entry plan's stated capacity sorts the 18 priced tools into groups. 7 charge per mailbox: the price on the page is for one inbox, and every additional inbox pays it again. 8 sell a bundle: the plan covers a stated number of mailboxes, from one up to fifty, and more mailboxes means a higher tier. 1 covers unlimited mailboxes on its entry plan and meters total daily volume instead. 2 do not state mailbox capacity on the entry plan in a form that can be read as a number.

Among the 7 per-mailbox tools, the median price is $29 per mailbox per month, with a range of $12 to $40.

Priced per mailbox

$29 for each mailbox, at the median

• 1 mailbox: $29
• 10 mailboxes: $290
• 30 mailboxes: $870

The bill is a straight line. Across 7 per-mailbox vendors, ten mailboxes cost a median of $290.

Priced by plan

One plan that covers ten or more

• Median for 10 mailboxes: $99
• Lowest: $7.50
• Highest: $1,190

The bill moves in steps across 7 vendors, and on the cheapest plans the daily warmup volume is shared by every inbox.

The difference is invisible to a founder warming one mailbox and decisive for a team running many. At the per-mailbox median, ten mailboxes cost $290 a month and thirty cost $870. Across the vendors in the ten-mailbox comparison below, the 7 that charge per mailbox cost a median of $290 for ten, and the 7 that cover ten with a single plan cost a median of $99. Cold email programs spread their volume across many mailboxes so that each one sends only a small number of emails a day. Under per-mailbox pricing, that practice multiplies the warmup bill without adding any sending volume.

The ten-mailbox comparison

Ten mailboxes is a modest setup: three or four domains with a few inboxes each. For each vendor, the study takes the cheapest published way to cover ten mailboxes, which is either the cheapest plan whose stated capacity is ten or more, or ten times the per-mailbox price, whichever is lower.

Across 14 vendors the cost runs from $7.50 to $1,190 a month, a spread of about 159 times. The median is $270 and the middle half falls between $104.25 and $372.50.

The cheapest three are MailWarm.io at $7.50 (one tier covering 50 mailboxes), Mailivery at $29 (one tier covering unlimited mailboxes) and EmailWarmer.io at $49 (one tier covering 25 mailboxes). The most expensive are Mailwarm at $549 (one tier covering 10 mailboxes) and InboxAlly at $1,190 (one tier covering 10 mailboxes). Four priced tools are left out because no published plan reaches ten mailboxes and the price is not per mailbox, or because capacity is not stated: Warmbox, Inboxy, Boost Inbox, Inbox Warmup.

Two cautions keep this table honest. First, the cheap end and the expensive end are not selling the same service. Plans that cover fifty or unlimited mailboxes for under $30 share one pool of daily warmup volume across every inbox, so each mailbox gets a thin slice. The most expensive vendor in the table prices by sender profile and by the number of its seed addresses a customer sends to each day, which is a different unit from a mailbox in a warmup network. Price per mailbox is a fair way to compare like with like, and only a starting point across models.

Second, these are list prices at the entry configuration. Several per-mailbox vendors quote volume bands in their plan notes, which lower the unit price at higher counts, and those were not applied.

Vendor-level detail, including those bands, is in the Mailreach pricing and Warmup Inbox pricing breakdowns. For head-to-head options, see the roundups of Warmbox alternatives, lemwarm alternatives and Mailreach alternatives.

How much warmup the entry plan includes

13 of the priced tools state a daily warmup volume on their entry plan. The median is 75 emails a day, the range is 40 to 200, and the single most common figure is 50. 5 tools publish no daily number and describe volume as managed by their algorithm.

For context, the daily figure is a ceiling on warmup traffic, not a recommendation. A new mailbox ramps from a handful of emails a day, and the cap matters mainly once the mailbox is mature and the warmup pool is being used to maintain reputation alongside real sending. Where the volume is shared across all mailboxes on a plan, as it is on the unlimited-mailbox and large-bundle plans, the per-mailbox figure is the shared number divided by the mailbox count. On a 200-a-day shared plan with ten mailboxes, that is 20 each.

Annual billing in warmup

11 warmup tools have both a month-to-month and an annual-plan rate on the record for their entry tier. The median annual discount is 21.1%, with the middle half between 18.6% and 24.6%, in line with the rest of the sales tool market. A twelve-month commitment is a poor fit for the first months of a new sending setup, when mailbox counts are still changing, and a reasonable one for a stable fleet.

How to choose on price

1. Count mailboxes first. One to three mailboxes: the per-mailbox vendors and the small bundles cost about the same, so choose on features. Ten or more: the pricing model decides the bill, and the ten-mailbox table above is the comparison that matters.
2. Divide shared volume by mailbox count. A plan with unlimited mailboxes and a shared daily pool is cheap per mailbox and thin per mailbox. Check that the per-mailbox slice is still a useful amount of warmup traffic.
3. Check what the sequencer already includes. In the same dataset, 42 of 146 email sending and sales engagement tools (28.8%) mention warmup in their own plan descriptions, which means warmup is bundled into the sending plan. A dedicated tool earns its price when it does something the bundled version does not, such as placement testing, provider-specific pools or reporting that an operator will actually read.
4. Treat warmup as one input. Warmup cannot rescue a bad list or a spammy message. Volume per mailbox, list quality and copy decide inbox placement for real campaigns.

The guide to the best email warmup tools for cold email teams covers the feature side of that decision. Teams that would rather hand off mailbox setup, warmup and sending altogether can see how RevenueFlow runs it on a free campaign.

Methodology

Population. The 20 tools categorised as email warmup in RevenueFlow's verified vendor dataset (386 tools in total) as of September 2026. Each record was read from the vendor's own pricing page and dated between 2026-08-28 and 2026-09-04. Cold email platforms that include warmup inside a sending plan are in a different category of the dataset and are not part of this study.

Starting price. The lowest monthly-equivalent figure among a tool's paid subscription tiers. One tool publishes only a yearly total, which was divided by twelve.

Capacity. Read from each tier's stated limits: a number followed by inboxes, mailboxes, email accounts or sender profiles is a bundle of that size, "per inbox", "per mailbox", "per email account" or "per slot" is a per-mailbox price, and "unlimited mailboxes" is unlimited. A provider name such as Office 365 is not a count. Placement-test plans and plans sized in credits have no mailbox capacity and were not used.

Ten-mailbox cost. The lower of the cheapest plan with capacity of ten or more and ten times the per-mailbox price. Volume bands that appear only in plan notes were ignored. Every row was read against its source record.

Limits. Twenty tools is a small population, so quartiles move when one vendor reprices. List prices only. The study compares price and stated limits, and says nothing about how well any tool improves inbox placement.

Pricing verified between 2026-08-28 and 2026-09-04. Verify current terms with the vendor before relying on them.