10 Best Email Warmup Tools

TL;DR

• If you’re sending cold email from a new domain, a warmup tool can help you avoid burning it on week one.

• For “warmup + outreach in one place,” Instantly is the most convenient.

• If you want a dedicated warmup tool with strong reviews, Warmup Inbox, Warmy, MailReach, and Mailivery all have active G2 review bases.

• Some popular names (like Warmbox) don’t have much review coverage on major sites, so I’d treat them as “try carefully.”

When I first started cold outreach, I assumed deliverability was mostly about SPF/DKIM/DMARC and “not being spammy.”

Then I watched perfectly normal emails land in spam anyway.

Warmup tools aren’t magic, but they’re a practical layer of defense: they create consistent, human-like inbox activity so your account doesn’t look like a brand-new sender blasting 100 emails out of nowhere. If you’re about to start outreach, warming up first is one of the easiest “boring things” that saves you pain later.

What Is an Email Warmup Tool?

An email warmup tool automatically sends and receives emails from your mailbox to a network of other mailboxes to help build sender reputation. It typically ramps volume gradually and simulates real engagement (opens, replies, moving messages out of spam). The goal is better inbox placement before you scale real outreach.

Guidelines We Used to Choose These Tools

Picking a warmup tool is less about fancy dashboards and more about avoiding deliverability problems.

Here’s what I used to shortlist:

• Warmup realism Do the interactions look like normal human email behavior, not machine patterns?

• Ease of setup Can you connect inboxes quickly without spending a day on troubleshooting?

• Visibility into deliverability Reputation signals, spam placement hints, blacklist monitoring, and practical guidance matter.

• Scaling controls Can you warm multiple inboxes safely with ramp-up and pacing controls?

• Pricing sanity Warmup is usually per inbox. Costs can explode if you scale.

Quick Overview of the Best Email Warmup Tools

Note: Some tools don’t have clean coverage on both G2 and Capterra. I’m not filling gaps with guesses.

Best Email Warmup Tools 

1. Warmup Inbox

Best for Solo founders and small teams who want a proven standalone warmup tool.

Warmup Inbox is one of the more reviewed warmup tools I see people stick with because it’s simple: connect an inbox, let it run, and monitor reputation improvements. G2 reviewers repeatedly mention ease of use and strong customer support.

Key features

• Automated warmup conversations to build reputation.

• Support for major inbox types like Google Workspace and Office 365.

• Deliverability and reputation monitoring signals.

• Strong support reputation based on reviewer feedback.

Pros and cons

• Reviewers frequently praise customer support and responsiveness.

• It’s easy to set up and works well for basic warmup needs.

• Some users mention setup details like ports can be annoying at first.

• If you want advanced diagnostics, it’s more “warmup first” than “deliverability lab.”

Pricing

Rating

• G2: 4.6

• Capterra: 5.0

Reviews

“Warmup Inbox has helped improve our email deliverability… enhanced our client communication…” – Antony M., G2

2. TrulyInbox

Best for Budget-focused warmup, especially if you want a free plan to test the concept.

TrulyInbox is positioned as a straightforward warmup tool with human-like sending patterns and a free tier. It’s not the deepest deliverability suite, but it’s attractive when you just want warmup without paying immediately.

Key features

• Free plan that supports warming one email account.

• Human-like warmup interactions with pacing controls.

• Paid tiers designed for more volume and scaling.

• G2 review presence with user feedback on usability.

Pros and cons

• The free plan makes it easy to test warmup workflows.

• G2 reviewers mention simple, user-friendly design.

• Some users mention Gmail integration issues and setup complexity.

• The free plan volume is low, so you can outgrow it quickly.

Pricing

Rating

• G2: 3.1

• Capterra: N/A

Reviews

“TrulyInbox… simple and user friendly design… Replies are humane…” – Nikhil N., G2

3. Instantly

Best for Outbound teams that want warmup bundled with sending and list workflows.

Instantly is primarily an outreach platform, but the built-in warmup is a big reason people choose it over stitching multiple tools together. On G2, it has a massive volume of reviews, and reviewers frequently mention usability and support.

Key features

• Unlimited email accounts with unlimited warmup on plans.

• Outreach sending limits that scale with plan tier.

• Workflow features around outreach and lead management.

• Large G2 review footprint compared to most warmup-only tools.

Pros and cons

• It’s convenient to keep warmup and outreach in one platform.

• G2 reviewers call out straightforward UI and setup.

• If you only want warmup and nothing else, it can feel like “too much tool.”

• Plan tiers and limits can matter a lot as you scale volume.

Pricing

Rating

• G2: 4.8

• Capterra: N/A

Reviews

“The software is easy to use, the support team is great, and the UX/UI is very straightforward…” – Dylan B., G2

4. MailReach

Best for Warmup plus deliverability monitoring, with lots of public social proof.

MailReach is one of the most frequently discussed warmup tools in cold email circles, and it has a clear G2 presence. Its own reviews page also links out to multiple third-party review sources.

Key features

• Automated email warmup process designed to be hands-off.

• Reputation and deliverability monitoring messaging.

• Supports multi-mailbox use cases (positioned for scale).

• Strong volume of G2 feedback compared to many warmup-only tools.

Pros and cons

• Real users mention noticeable inbox placement improvements.

• Some testimonials specifically compare outcomes vs other warmup tools.

• If you’re cost-sensitive, per-inbox pricing can feel expensive at scale.

• Some feedback online is marketing-heavy, so I’d rely on G2/Capterra links first.

Pricing

Rating

• G2: 4.7

• Capterra: 5.0

Reviews

“Their automated email warmup process is a lifesaver… completely hands-off…” – Ian T., G2

5. Warmy

Best for Teams that want warmup plus more deliverability-focused tooling and testing.

Warmy has one of the most active review footprints on G2 among warmup/deliverability tools. It’s often chosen by agencies and teams who care about more than just “run warmup in the background.”

Key features

• Automated warm-up process with multi-inbox management.

• Inbox placement and mailbox health testing on plans.

• Custom warmup settings and warmup language options.

• Deliverability tooling positioned beyond basic warmup.

Pros and cons

• Strong volume of verified G2 reviews and consistently high ratings.

• Reviewers often mention support as a standout.

• Some users say setup can take time if your email auth is messy.

• Pricing can feel high for smaller teams depending on plan needs.

Pricing

Rating

• G2: 4.8

• Capterra: 4.0

Reviews

“I find Warmy incredibly valuable… warm up new email inboxes and domains… simple and easy to use…” – Mark A., G2

6. Mailivery

Best for Teams that want an “unlimited inboxes” pricing model for warmup.

Mailivery is interesting because it leans into “unlimited email accounts” on its plans, which can be attractive for agencies or teams warming multiple domains. It also has an active G2 page with reviewer quotes that talk about deliverability improvements and useful extras like blacklist monitoring.

Key features

• Unlimited email accounts on plans, with volume limits based on plan.

• Blacklist monitoring and spam-words checking called out by reviewers.

• Custom warm-up templates supported on higher tiers.

• G2 reviews cite improved inbox placement and response rates.

Pros and cons

• The “unlimited inboxes” approach can be cost-efficient for multi-inbox teams.

• Reviewers mention deliverability improvements and useful monitoring features.

• Reviewers also ask for more detailed analytics.

• Your real limit becomes daily interactions, not number of mailboxes.

Pricing

Rating

• G2: 4.5

• Capterra: N/A

Reviews

“What I like best is that it helped dig my emails out of the spam box…” – Kim P., G2

7. Lemwarm

Best for People who want a dedicated warmup product from the lemlist ecosystem.

Lemwarm is positioned as a standalone warm-up and deliverability booster, with reports and technical setup checks. Pricing is clearly per email inbox, and it’s one of the more “structured” warmup offerings in terms of features like deliverability reports and alerts.

Key features

• Automatic email warm-up with a warmup network.

• Technical setup checks to catch configuration issues early.

• Deliverability reports and alerts for monitoring progress.

• Warm up real email templates on higher tiers.

Pros and cons

• The pricing and plan structure is straightforward per inbox.

• It’s designed specifically around warmup and deliverability workflows.

• It has limited review visibility on G2 and Capterra as a standalone product.

• If you want tons of third‑party feedback, you may find the public review footprint thinner than competitors.

Pricing

Rating

• G2: N/A

• Capterra: N/A

Reviews

“Setting up Lemwarm was super straightforward. Within a few clicks, I was up and running. What really impressed me early was the customization options” – Rajat K, kipplo

8. Mailwarm

Best for People who want a classic warmup tool and care about spam score tracking.

Mailwarm is one of those tools that’s been around long enough to feel “standard,” and it leans into warmup plus spam score monitoring. Its pricing is clearly positioned for individuals and teams based on daily email volume and number of accounts.

Key features

• Warmup plans tiered by daily email volume and number of warmed accounts.

• “Real-time spam score tracking” mentioned by reviewers.

• Consulting support appears on higher tier plan features.

• Strong focus on inbox placement for cold outreach.

Pros and cons

• Reviewers mention reliable warmup outcomes over time.

• Pricing and tiers are simple to understand.

• Some reviewers say deliverability drops when warmup is paused, so it feels “always on.”

• Managing multiple domains at scale could be smoother, based on reviewer feedback.

Pricing

Rating

• G2: 5.0

• Capterra: 5.0

Reviews

“What I like most… consistent and reliable… deliverability significantly improves…”– Verified User, G2

“The main downside is… once I stop… deliverability tends to decrease…” – Verified User, G2

9. Warmbox

Best for People who want a simple warmup tool and a low entry price.

Warmbox’s official pricing starts low, but the biggest issue is the public review footprint on trusted sites. That doesn’t mean it’s bad, but it does mean you’re relying more on trials and firsthand testing than on verified reviews.

Key features

• Warmup plans starting at $15/month.

• Tiered by number of inboxes and daily email volume.

• Marketing emphasizes inbox placement and warmup automation.

• Limited third-party review coverage on major review sites.

Pros and cons

• Low starting cost makes it easy to try.

• Plans scale by inbox count and volume in a predictable way.

• There are few trustworthy third-party reviews available publicly.

• If you need confidence from verified reviews, this is the weakest option on that front.

Pricing

Rating

• G2 N/A

• Capterra N/A

Reviews

“Warmbox Simple and straightforward… Multiple warmup recipes… Works with any email provider…” – Reddit user

10. Folderly

Best for Teams that want a more enterprise-style deliverability platform with warmup-style maintenance.

Folderly is less “just warmup” and more “deliverability platform,” and that shows in pricing and positioning. On G2, reviewers mention consulting-style support and diagnostics-type workflows.

Key features

• Deliverability tooling focused on inbox placement and diagnostics.

• Higher-touch support and client success manager mentioned in reviews.

• Pricing based on number of connected mailboxes.

• Strong verified review presence on G2 and Capterra.

Pros and cons

• Reviewers mention it being reliable and support being consultative.

• It’s designed for ongoing deliverability maintenance, not just “warm up then stop.”

• Pricing is much higher than lightweight warmup tools.

• It can be more tool than you need if you’re just starting cold outreach.

Pricing

Rating

• G2: 4.8

• Capterra: 5.0

Reviews

“Of all the tools… Folderly was definitely the best and most reliable…” – Svitlana T., G2

Conclusion

If you’re sending cold email, warmup is basically your “insurance policy” against blowing up a new domain.

My personal way to choose is simple:

• If you want the easiest all-in-one path, Instantly is hard to beat. 

• If you want a straightforward standalone warmup with lots of support praise, Warmup Inbox is the safest bet.

• If you want deeper deliverability tooling, Warmy and Folderly are the more “serious” options.

I hope my experience helps you pick a tool that keeps your emails out of spam and your domain alive long enough to actually book meetings.