---
title: "Best Email Warmup Tools (2026): 13 Options Compared"
description: "The best email warmup tools in 2026: what OneGTM uses (Instantly warmup on ScaledMail inboxes), then Smartlead, lemwarm, MailReach, Warmy and more with pricing."
url: https://getaob.com/email-warmup-tools
---

# Best email warmup tools (2026): what we use, and what warmup cannot fix

Email warmup builds a new mailbox's sending reputation by gradually increasing volume and generating positive engagement before you send cold email at full speed. It helps new domains and mailboxes get started, but it does not fix bad lists, broken DNS, or copy that people mark as spam.

Below is the setup OneGTM uses for client sending, then the other warmup and deliverability tools worth knowing, with what each costs. We have no reseller deals with anyone listed.

By [Garrett Wolfe](https://garrettawolfe.com), founder of OneGTM (Clay Artisan Solutions Partner) and former GTM engineer at Unify. Updated October 12, 2026.

Key takeaways

- Most cold email platforms now include warmup, so a separate tool is often unnecessary.
- Our setup is ScaledMail inboxes warmed and sent through Instantly, with SPF, DKIM, and DMARC checked first.
- Plan on about two weeks of warmup before new mailboxes send at volume, and keep volume per mailbox low.
- Warmup cannot save a bad list. Verified emails and relevant copy matter more.

## The warmup setup OneGTM uses

We separate infrastructure from sending. ScaledMail provides the mailboxes and domain setup, and Instantly warms them and runs the campaigns. We check every domain with our [free deliverability checker](https://getaob.com/email-deliverability-checker) before it sends.

### [Instantly](https://instantly.ai)

OneGTM uses this

Cold email platform with unlimited connected mailboxes and unlimited warmup through its shared warmup pool on every plan. Paid premium pools of aged Google and Microsoft accounts are available.

**Best for:** Warmup and sending in one tool

**Pricing:** Outreach from $47/month, warmup included. Premium warmup pools from $500/month per workspace.

### [ScaledMail](https://www.scaledmail.com)

OneGTM uses this

Sets up and manages pre-configured Google Workspace, Microsoft 365, and SMTP inboxes for cold email, including domains and SPF, DKIM, and DMARC records. It does not warm mailboxes itself, so we pair it with Instantly.

**Best for:** Mailbox and domain infrastructure at scale

**Pricing:** Google Workspace $3.50 per mailbox per month; Microsoft $50 per domain per month for 25 mailboxes.

## Other email warmup and deliverability tools

Sequencers with built-in warmup come first, then standalone warmup tools, then deliverability and infrastructure products that pair with them.

### [Smartlead](https://www.smartlead.ai)

Cold email platform with unlimited mailboxes, automatic inbox rotation, and unlimited warmup on every plan.

**Best for:** Agencies and teams sending from many mailboxes

**Pricing:** Base $39/month; free trial.

### [lemlist (lemwarm)](https://www.lemlist.com/lemwarm)

lemwarm is lemlist's warmup feature. It is no longer sold on its own and comes with every lemlist plan.

**Best for:** Teams already using lemlist for multichannel outreach

**Pricing:** lemlist Email plan $69/month; 14-day free trial.

### [Apollo](https://www.apollo.io/product/email-deliverability)

Apollo's deliverability suite includes mailbox warmup on paid plans, alongside its database and sequencer.

**Best for:** Teams already sending from Apollo

**Pricing:** Included from the Basic plan, $49/seat/month billed annually.

### [Woodpecker](https://woodpecker.co)

Cold email sequencer that includes free warm-up for a set number of mailboxes on each plan.

**Best for:** Small teams sending personalized sequences

**Pricing:** Usage-based on contacted prospects; check current pricing. 14-day trial.

### [MailReach](https://www.mailreach.co)

Standalone warmup through a network of high-reputation accounts, plus inbox placement (spam) tests.

**Best for:** Warming specific mailboxes and testing placement

**Pricing:** $19.50 per mailbox per month.

### [Warmy.io](https://www.warmy.io)

Automated warmup with deliverability extras such as seed-list tests, DMARC monitoring, and email verification.

**Best for:** Teams that want warmup and monitoring together

**Pricing:** From $49/month; 7-day free trial.

### [Warmbox](https://warmbox.ai)

Warmup by exchanging emails across a network that spans 11+ providers, including SMTP services like SendGrid and Amazon SES.

**Best for:** Warming non-Google and non-Microsoft senders

**Pricing:** Solo $19/month for one inbox.

### [Mailwarm](https://www.mailwarm.com)

Warmup through a network of aged inboxes, with spam score monitoring and calls with a deliverability expert on every plan.

**Best for:** Teams that want hands-on deliverability help

**Pricing:** Starter $69/month billed annually for one mailbox.

### [EmailBison](https://emailbison.com)

Cold email platform on single-tenant infrastructure with dedicated IPs and warmup built in, so other customers cannot affect your reputation.

**Best for:** High-volume senders who want isolated infrastructure

**Pricing:** $599/month for 500,000 emails a month.

### [Folderly](https://folderly.com)

Deliverability platform that finds and fixes technical and content problems hurting inbox placement, then monitors delivery.

**Best for:** Diagnosing an existing deliverability problem

**Pricing:** $96 per mailbox per month billed yearly; free placement tests and alerts.

### [Maildoso](https://maildoso.ai)

SMTP mailboxes built for outbound with IP rotation. Warmup is not included, so it pairs with a tool like Instantly.

**Best for:** Low-cost outbound mailboxes

**Pricing:** $75/month for 30 mailboxes.

Prices are from each vendor's site as of October 2026 and change often, so check before you buy. This is an opinionated list, not a paid ranking.

## Email warmup tools compared

| Tool | Best for | Starting price |
| --- | --- | --- |
| Instantly (OneGTM uses) | Warmup and sending in one tool | Outreach from $47/month, warmup included |
| ScaledMail (OneGTM uses) | Mailbox and domain infrastructure at scale | Google Workspace $3.50 per mailbox per month |
| Smartlead | Agencies and teams sending from many mailboxes | Base $39/month |
| lemlist (lemwarm) | Teams already using lemlist for multichannel outreach | lemlist Email plan $69/month |
| Apollo | Teams already sending from Apollo | Included from the Basic plan, $49/seat/month billed annually |
| Woodpecker | Small teams sending personalized sequences | Usage-based on contacted prospects |
| MailReach | Warming specific mailboxes and testing placement | $19.50 per mailbox per month |
| Warmy.io | Teams that want warmup and monitoring together | From $49/month |
| Warmbox | Warming non-Google and non-Microsoft senders | Solo $19/month for one inbox |
| Mailwarm | Teams that want hands-on deliverability help | Starter $69/month billed annually for one mailbox |
| EmailBison | High-volume senders who want isolated infrastructure | $599/month for 500,000 emails a month |
| Folderly | Diagnosing an existing deliverability problem | $96 per mailbox per month billed yearly |
| Maildoso | Low-cost outbound mailboxes | $75/month for 30 mailboxes |

Starting prices as published by each vendor in October 2026.

## What email warmup does and does not do

Warmup tools send and reply to emails between mailboxes in a network, open them, and pull them out of spam, so a new mailbox builds a history of normal, positive activity. That gives mailbox providers a reason to trust it when real campaigns start.

It does not replace the basics. You still need correct [SPF](https://getaob.com/gtm-glossary#spf), [DKIM](https://getaob.com/gtm-glossary#dkim), and [DMARC](https://getaob.com/gtm-glossary#dmarc) records, verified email addresses, a low [bounce rate](https://getaob.com/gtm-glossary#bounce-rate), and copy people actually want to answer. Neither Google nor Microsoft has published guidance endorsing warmup networks, so treat warmup as a ramp, not a shield.

## How we warm new mailboxes

- Send from secondary domains, never your main company domain.
- Set up SPF, DKIM, and DMARC on day one, and test them with the [deliverability checker](https://getaob.com/email-deliverability-checker).
- Warm each mailbox for about two weeks before campaigns start, and keep warmup running afterward at a lower level.
- Keep daily cold volume per mailbox low and add mailboxes to grow volume instead of pushing each one harder.
- Verify every address before sending and watch [inbox placement](https://getaob.com/gtm-glossary#inbox-placement), not just open rates.

## When it makes sense to get help with cold email infrastructure

Warmup is the easy part. The mistakes that hurt are made earlier and later: sending from the main domain, missing DMARC, too many emails per mailbox, unverified lists, and no one watching placement until meetings dry up.

OneGTM sets up the domains, mailboxes, authentication, and warmup, then runs campaigns with volume and list quality kept inside safe limits. You own every domain and mailbox.

- You are launching cold email for the first time and want it right on day one.
- Open or reply rates fell suddenly and you suspect spam placement.
- You need to scale from a few mailboxes to dozens without burning domains.
- Your main company domain is already showing up in spam.

Book a deliverability review

## Email warmup tools FAQ

### What is the best email warmup tool?

For most cold email teams the best option is the warmup built into their sending platform, such as Instantly or Smartlead, because it is included and runs alongside campaigns. OneGTM warms ScaledMail inboxes through Instantly. Standalone tools like MailReach, Warmy, and Warmbox make sense when you need to warm mailboxes outside a sequencer.

### How long should I warm up a new email account?

Plan on about two weeks of warmup before sending cold email at volume from a new mailbox, then keep a lower level of warmup running. New domains and Microsoft mailboxes can take longer.

### Is email warmup still necessary?

For new mailboxes and domains, yes. Warmup builds the sending history that providers look for. It will not fix a bad list, missing authentication records, or spammy copy, so it works best alongside verified data and good DNS setup.

### Do I need a separate warmup tool if I use Instantly or Smartlead?

Usually not. Both include unlimited warmup on their plans. A separate tool is useful for mailboxes you send from elsewhere or when you want extra placement testing.

### Is ScaledMail a warmup tool?

No. ScaledMail provides pre-configured Google Workspace, Microsoft 365, and SMTP inboxes with domain and DNS setup. You still warm those inboxes in a sending platform such as Instantly.

### Does warmup prevent emails from going to spam?

It lowers the risk for new mailboxes but does not guarantee inbox placement. Authentication, list quality, bounce rate, sending volume, and how recipients react to your emails all matter more over time.

### Should I hire someone to set up cold email infrastructure?

If you are sending low volume from a handful of mailboxes, you can set it up yourself with a sequencer that includes warmup. It is worth getting help when you need dozens of mailboxes, when deliverability has already dropped, or when a mistake on your main domain would be costly.

Want cold email infrastructure set up the right way?

## Related

- [Free email deliverability checker](https://getaob.com/email-deliverability-checker): Test SPF, DKIM, DMARC, and MX for any domain and scan cold email copy for spam triggers.
- [Signal-based outbound agency](https://getaob.com/outbound-agency): Cold email and LinkedIn systems triggered by real buying signals.
- [Best B2B prospecting tools](https://getaob.com/b2b-prospecting-tools): Prospecting tools for lists, signals, and outreach, with the ones OneGTM uses first.
- [Best data enrichment tools](https://getaob.com/data-enrichment-tools): The enrichment stack OneGTM runs, plus the main alternatives and what each costs.
- [B2B lead generation agency](https://getaob.com/lead-generation-agency): Lead gen systems you own instead of one-off lists.

## Get a deliverability review

Tell us what you're building. We reply the same day.

Book a call at [getaob.com/#contact](https://getaob.com/#contact) or email [team@getaob.com](mailto:team@getaob.com).