The best email warmuptools in 2026.

We ranked HotHawk against ten standalone email warmup tools on the things that actually decide one: what the pool is made of, whether warmup is bundled or billed per inbox, the placement testing, and the real cost. Here is how they stack up, and which one fits which setup.

11 tools compared · Last updated June 2026 · No sponsored placements

HotHawk is cold email software for serious outbound teams.

Special offer

Get 50% more sending, FREE.

50% extra sending on any plan, every month for as long as you're with us.

On this page

Our top picks

No single warmer wins for everyone, and several of these are genuinely good at one job. Here is the short version before the detail.

Best if your sender includes itHotHawkNative warmup on a disclosed pool of real Google and Microsoft inboxes, free inside a full sender at one flat price.Best standalone warmupMailReachReal Google and Microsoft inbox network paired with a mature spam tester that fires at 30+ seed inboxes.Cheapest entry pointWarmup InboxReal-account warmup from $15 per inbox a month on annual billing, with a 7-day trial and no card.Cheapest flat-rate warmupTrulyInboxCharges by daily volume with unlimited accounts and a free-forever tier, though that daily volume is shared across every account.Best warmup as an APIMailiveryA proper REST warmup API you can embed, on flat pricing by volume across unlimited mailboxes.

How we tested

Our method.

We judged every tool on what decides whether warmup helps: the make-up of the pool and how pure the providers are, whether warmup is bundled into a sender or billed per inbox, the deliverability and placement testing on offer, the control you get (mailbox quarantine, daily limits), and the real cost.

One thing to be straight about: a few of these warm against real Google and Microsoft inboxes too, so HotHawk is not unique there. What it does differently is bundle warmup natively inside a full sender, on a disclosed pool of real Google and Microsoft inboxes only.

Pricing and features come from each provider’s own website as of June 2026. Pool sizes are vendor-stated and unverified, and several conflict across sources. Weak points reflect themes in public user reviews, not absolute statements of fact. HotHawk is our own product, so we have put it first, and we have said plainly where the others genuinely beat us. No tool paid to be here, and there are no affiliate links.

The 11 tools, side by side.

The headline facts first. The full write-up on each tool, with where it wins and where it falls short, is underneath.

Cold email tools compared feature by feature.
Tool	Google/MS only?	Pool size	Standalone or bundled	Daily warmup volume	From	Placement testing	Free trial
HotHawkOur pick		50,000+	Bundled in sender	Per mailbox, no shared cap	$97/mo	Not the focus	7-day
MailReach	Mostly G/MS	30,000+	Standalone	~100/day per inbox	$25/inbox	30+ seed inboxes
Warmy.io		1M+ stated	Standalone	Per inbox	~$49/inbox	Seed list	7-day
Warmup Inbox		15,000+	Standalone	75–1,000 per inbox	$15/inbox	Spam checker	7-day
TrulyInbox		~10,000	Standalone	Shared pool (200/day Starter)	Free / $22/mo
Lemwarm		20,000+ domains	Free in Lemlist	40/day (Essential)	$29/inbox		With Lemlist
Mailivery		100K+ disputed	Standalone + API	Shared pool (200/day Starter)	$29/mo		7-day
Warmbox		~35,000	Standalone	Per plan (50–500)	$15/mo	Partial	Unclear
MailToaster		Undisclosed	Standalone	Per inbox	$29/inbox	Partial
Mailwarm		50,000+ stated	Standalone	Per plan (50–500)	$69/mo	Partial
Maildoso		AI bots, no pool	Infra + add-on	100/day per mailbox	Add-on $160/mo	Health checks

Figures are from each provider’s own website as of June 2026. On daily warmup volume, the "shared pool" tools (TrulyInbox, Mailivery) split one daily allowance across every connected account, so their entry plans warm 200 emails a day in total however many accounts you connect, where per-inbox tools and HotHawk warm each mailbox to its own limit. Pool sizes are vendor-stated and unverified, and several conflict across sources (Mailivery’s 100K+ is disputed down to about 30k; MailReach and Warmup Inbox show different pool numbers across listings). "Standalone" means a tool you bolt onto a separate sender. Prices change, so check each provider for the latest.

The 11 best email warmup tools, ranked.

HotHawk

from $97/moOur pick

Native warmup on a disclosed pool of real Google and Microsoft inboxes, free inside a full sender.

Where it wins. Warmup runs against 50,000+ real Google and Microsoft inboxes only, never SMTP accounts or bots, with AI holding genuine business-relevant conversations between them. Risky mailboxes are pulled from the pool and a bouncing mailbox is suspended on the spot, and each mailbox warms to its own daily limit with no shared pool to split between accounts, so the warmup keeps up however many you connect. It is included on every plan at $97 a month all-in, so warmup is not a separate line on your bill, and there is a 7-day trial.

The trade-off. HotHawk is a full sender with warmup built in, not a standalone tool you bolt onto something else. If you already run a sender you are happy with and only want warmup added, a per-inbox tool below will sit alongside it more neatly. The honest read is that if your sender already includes native warmup, you probably do not need a separate one at all.

Start free trial

MailReach

from $25/inbox

The strongest standalone warmer, with a mature inbox-placement tester next to it.

Where it wins. Warms against a network of 30,000+ accounts that are mostly real Google and Microsoft inboxes, with multi-turn reply threads that read like real email. The spam tester fires at 30+ seed inboxes and breaks placement down by provider, which is more diagnostic depth than most warmers carry.

Where it falls short. Per-inbox pricing around $25 a mailbox gets steep for small teams, there is no free trial of the warmer, and the spam-test credits run out and cost extra. A few users note the dashboard placement scores do not always match their real campaign open rates.

Visit website

Warmy.io

from ~$49/inbox

The most feature-complete standalone warmer, if you can find the price.

Where it wins. Real-inbox warmup with AI-written messages on any topic across 30+ languages, plus seed-list placement testing, Google Postmaster integration, and support for Yahoo, SES and Zoho that a Google and Microsoft pool leaves out. It splits B2B and B2C warmup, which few rivals do.

Where it falls short. Per-inbox pricing punishes growth, and 19 inboxes can run past $2,000 a month. Worse, the public prices were pulled in 2026, so the page now says "volume based" and routes you to a demo. Reviewers also flag Microsoft and Outlook warmup quality.

Visit website

Warmup Inbox

from $15/inbox

The budget pick, real accounts from $15 an inbox with a no-card trial.

Where it wins. Warms against a real-account network that includes Google and Microsoft inboxes, from $15 per inbox a month on annual billing, the lowest serious entry point here. Higher tiers add language warmup across 12 languages and ESP-specific warmup, and the 7-day trial needs no card.

Where it falls short. The disclosed network of 15,000+ is smaller than several rivals, the analytics are basic, and the per-inbox model climbs fast at scale (running 100 domains works out near $4,700 a month by one third-party estimate).

Visit website

TrulyInbox

from Free / $22/mo

Charges by volume, not per inbox, so connecting accounts stays cheap. This is Saleshandy’s warmup engine.

Where it wins. You pay for daily warmup volume and connect unlimited accounts, which is the cheapest model if you do not need much volume per inbox. There is a free-forever tier (10 a day), four AI warmup strategies, and a deliverability score with ESP-level analytics. Worth knowing this is the engine Saleshandy bundles, so its warmup is TrulyInbox.

Where it falls short. That daily volume is shared across every account, so the $22 plan warms 200 emails a day in total, and a lot of inboxes each get a trickle. The free tier is too small to warm a real account, the network sits around 10,000 mixed-provider accounts rather than Google and Microsoft only, and white-label is reserved for the top Scale+ tiers.

Visit website

Lemwarm

from $29/inbox

Free inside Lemlist, real inboxes with human-like replies, pricey on its own.

Where it wins. Warms across 20,000+ healthy domains with real inboxes and threaded human-like replies, no bots, and it is included free on any paid Lemlist plan. If you already run Lemlist for outreach, the warmup just runs inside your campaigns.

Where it falls short. Bought standalone it is $29 to $49 an inbox, among the dearer warmers, and the network mixes providers rather than sticking to Google and Microsoft business inboxes. The Essential plan caps you at 40 a day, and there is no true seed-list placement testing inside Lemwarm.

Visit website

Mailivery

from $29/mo

A peer-to-peer warmer with a real warmup API. This is Woodpecker’s warmup engine.

Where it wins. A genuine REST API to connect mailboxes, start and pause warmup and adjust volume, which makes it the pick if you want to embed warmup in your own product. Flat pricing by daily volume across unlimited mailboxes, plus placement testing and blacklist monitoring across 70+ lists. It powers warmup inside Woodpecker (alongside Warmy).

Where it falls short. The headline 100K+ pool is vendor-stated and disputed down to about 30k by a rival, and it is a mixed-provider network, not Google and Microsoft only. Shared daily volume gets thin past five or six inboxes, and there is a rocky AppSumo reliability history the founder says has since been rebuilt.

Visit website

Warmbox

from $15/mo

Automation-first warmup with lots of ramp control, on a mixed network.

Where it wins. Customisable warmup styles (growth, flat, random or fully custom) with GPT-4 and hybrid content, across a broad ESP list (Yahoo, iCloud, AOL, Yandex, SES and more), from a private network put at around 35,000 inboxes.

Where it falls short. It is a mixed network, not Google and Microsoft only, which is lower signal for B2B deliverability. It bills per team member on top of the plan, there is no clearly advertised trial, and the independent review footprint is close to nonexistent, so you are leaning on vendor testimonials.

Visit website

MailToaster

from $29/inbox

A simple flat-rate P2P warmer, integrated into Reply.io.

It is the warmup engine integrated into Reply.io, which gives one MailToaster seat free per Reply email seat.

Where it wins. One flat price, $29 an inbox a month ($26 on annual), with peer-to-peer warmup, spam rescue and an email health checker that runs SPF, DKIM and DMARC on connect. If you already pay for Reply.io, you get it free with your seats.

Where it falls short. No pool size is disclosed anywhere, the content is GPT-3 generation rather than a current model, and the independent review base is effectively zero. Reviewers using it as Reply.io’s warmup report inconsistent placement, and the marketing pages look stale.

Visit website

Mailwarm

from $69/mo

A premium single-inbox warmer with deliverability experts on the plan.

Where it wins. A roughly two-minute setup, a real-inbox network, and deliverability-expert calls included on every plan, so it suits a solo founder who wants warmup handled for them on one inbox.

Where it falls short. It is $69 to $479 a month by inbox count with no free trial, so you pay before you can test it, and the review base is sparse and aging (about 14 G2 reviews). One independent test flagged poor Outlook and Microsoft results, and a few reviewers call the simulated replies robotic.

Visit website

Maildoso

from Add-on $160/mo

The odd one out: this is sending infrastructure with a bot-warmup add-on, not a real-inbox warmer.

Where it wins. It sells the layer below warmup: done-for-you domains and SMTP or Google Workspace mailboxes from about $0.49 each, ready in minutes, with self-healing mailboxes and IP rotation. As infrastructure it is genuinely useful, and it can sit underneath a sender like HotHawk.

Where it falls short. Its warmup is the architectural opposite of the others here: an AI-browser-bot add-on at $160 to $2,000 a month, not a real-inbox network, and Gmail and Outlook only with no Microsoft 365 mailboxes at any tier. If you came here for a warmer, this is not one in the same sense as the rest.

Visit website

Email warmup, answered.

What is the best email warmup tool in 2026?

It depends on what you are bolting it onto. For standalone warmup with proper diagnostics, MailReach is the pick, and Warmy.io is the most feature-rich if you can get a price out of it. Warmup Inbox is the cheapest entry at $15 an inbox, and TrulyInbox is the cheapest flat model if you only need light warmup, since it charges by volume rather than per inbox, though that volume is shared across every account. If you want warmup that comes built into the sender rather than as a separate tool, that is HotHawk.

Do you need a separate email warmup tool?

Often not. If your sending platform already includes native warmup, a second tool is usually a duplicate cost. Most senders that bundle warmup actually run one of these engines under the hood: Saleshandy uses TrulyInbox, Woodpecker uses Mailivery, and Reply.io uses MailToaster. HotHawk runs its own native warmup. The case for a standalone tool is when your sender has no warmup, or you want diagnostics it does not offer.

What is the cheapest email warmup tool?

On a per-inbox basis, Warmup Inbox is the cheapest serious option at $15 per inbox a month on annual billing. TrulyInbox charges by daily volume with unlimited accounts rather than per inbox, so it can work out cheaper, but the catch is that the volume is shared across all your accounts, so the cheap plans only suit light warmup, not warming a lot of inboxes hard. It has a free-forever tier (10 warmup emails a day) to start on, though that is too small for a real sending account.

Do email warmup tools actually work, and are they safe?

A warmer builds engagement on a new domain gradually and keeps a sender active, which supports your reputation. It is not a fix for a bad list, broken SPF, DKIM or DMARC, or a domain that is already burned, and no tool can promise inbox placement. The safer ones use real inboxes, ramp slowly, set per-mailbox limits and pull bad mailboxes from the pool. Push the volume too hard, too soon and warmup can hurt rather than help.

Which warmup tools use real inboxes versus bots?

Most of the tools here warm against networks of real inboxes, including MailReach, Warmy, Warmup Inbox, Lemwarm, TrulyInbox, Mailivery and Mailwarm. HotHawk warms only against real Google and Microsoft inboxes. The exception is Maildoso, whose add-on warmup uses AI browser bots that perform in-browser actions rather than a real-inbox pool, which is why we have flagged it as the odd one out.

Comparison based on publicly available information from each provider’s website, accurate as of June 2026. Pricing and features change, so check each provider for the latest. Pool sizes are vendor-stated and unverified. Weak points reflect themes in public user reviews, not absolute statements of fact. All product names are trademarks of their respective owners; HotHawk is not affiliated with or endorsed by them. Last updated June 2026.

Send cold emails that get delivered.Never miss a positive reply.

Serious deliverability paired with the best reply management in the market.

Start your 7 day free trial

No credit card required.