16 Feb 5 Best Email Warmup Platforms to Protect Deliverability

Most cold email campaigns fail before they even get started. That’s because many sales teams focus too much on volume rather than deliverability. Remember, once email deliverability starts dropping, a domino effect ensues, taking your sender reputation down with it.

The best way to protect your sender reputation and email deliverability is to add your inboxes to an email warm-up platform. We’re here to help you choose the best ones.

How to Choose the Best Email Warmup Platforms?

When choosing an email warmup platform, you need to ensure that the warmup pool:

• Is made up of real, active, high-quality inboxes across Gmail and Microsoft.
• Can set schedules and throttles that match human-like email activity.
• Supports automatic pauses or safety controls.

It’s also essential to think about scalability. So, don’t look at the features alone. You should also consider the following questions:

• Does the email warmup platform charge you per inbox?
• How many warmups can you send daily?
• Do you have to pay for a higher-tier plan to get added to a premium warm-up pool?

5 Best Email Warmup Platforms for Protecting Deliverability

With hundreds of email warmup platforms available on the market, you’d think it would be easy to find ones that work. Instead, you see people like this saying warmup is a gimmick you pay for.

What this person is saying is 100% true. Many warmup platforms do more harm than good. To help you sift through the bad ones, we’ve compiled a list of the five best email warm-up platforms for cold outreach campaigns.

Instantly.ai

When we tested Instantly Email Warmup, it was clear how much deliverability was a priority. They don’t charge users an extra $30/month for their warmup. Instead, they included it with every plan. And you can add unlimited inboxes, so you won’t have any problems scaling.

It gets even better if you buy inboxes through Instantly DFY Email Setup. Those accounts are automatically added to Instantly’s Premium Warmup Pool for free, which is built on high-quality Microsoft and Google accounts and runs on stricter warmup rules to keep deliverability pristine.

What we love about Instanly email warmup:

• Continuous email verification, so low-quality accounts don’t drag down everyone else.
• Automatic bounce monitoring that disables warmup and bans bad actors from the pool.
• Plain-text warmup emails by default, keeping content safe and reducing risks.
• No links, attachments, or sign-up forms in warmup traffic, so nothing triggers filters.
• You get $500/month in value for free with Instantly’s premium email warmup pools.

Pricing: Instantly email warmup is free with every outreach plan, which starts at $47/month.

Apollo Email Warmup

Apollo has been an industry standard for prospecting and outreach for a long time, for good reason. And in 2025, they brought back their warm-up pool. If you’re looking to scale prospecting volume + warmup, Apollo is one of the best choices.

You have three options for their email warmup pool: Progressive, Flat, and Randomized. But as a rule of thumb, you’d probably want to stick with Progressive, since it gradually ramps up sending volume.

What we love about Apollo Email Warmup:

• Apollo warmup is free for your first inbox.
• Scaling isn’t as expensive as standalone warmup tools.
• Warmup vs ramp up is separated (New ones get warmup, older ones get Ramp Up)
• You can get a warmup for free, even with their free forever plan.
• You control your daily warmup range and reply rate with Apollo’s recommended defaults: minimum 10, maximum 40, and a 30% reply rate.

Pricing: Apollo includes Email Warmup for one inbox at no extra charge. If you want to warm up multiple inboxes, Apollo charges monthly credits per inbox. Here’s a breakdown:

Boxward

Boxward is a platform dedicated solely to warumps—no outreach, no prospecting. They also include many deliverability monitoring tools, such as inbox placement, spam correction, and detailed analytics of email activity.

What’s great about Boxward is that it lets users add any type of email account, not just Gmail or Outlook. It’s also a solid option for bringing back inboxes that used to perform well but have started slipping in deliverability.

What we love about Boxward:

• Different warmup algorithms depending on email health and sender reputation.
• Personalized emails in warmups using merge fields, so each email is unique.
• Detailed analytics reporting.
• Deliverability monitoring.
• Warmup providers for Sendgrid, Mailgun, Gmail, Outlook, and Microsoft 365.

Pricing: Boxward charges $19 per inbox (but they currently have a promo that’s $9/month). Scaling might be an issue. So, Boxward might be better for recovering previously high-value email accounts.

Mailivery

Mailivery is an email warm-up platform that’s perfect for scaling outreach, as it lets you add unlimited inboxes. The only caveat is that warmups are shared per inbox. And you only get higher response rates in your warmups if you go to higher-tier plans.

Aside from warmup, you also get blacklist monitoring, email verification, and spam word checkers. If you’re a power user who works with high-volume sending, they also have API integrations for your dev team to work with.

What we love about Mailivery:

• Unlimited inboxes with every plan.
• Fully customizable sending patterns.
• You get recommendations for blacklist delisting.
• Real peer-to-peer email accounts in the warmup pool.

Pricing: Mailivery pricing starts at $29/month, with 100 warm-up emails shared across accounts. If you’re doing 30-ish warmups per day, you can realistically do with 3 to 4 inboxes. Anymore than that, we’d recommend you go for Professional, which is $79/month.

MailReach

What’s great about MailReach is the emphasis on quality signals. Warmup interactions include opens, positive replies, being marked important, and removing messages from spam, plus you can track reputation by provider and get alerts when things shift.

It’s also flexible in setup, since it’s compatible with any email provider that supports SMTP, not just Google or Microsoft. And you can get started in less than 2 minutes. All you need to do is connect your account, and MailReach takes care of the rest.

What we love about MailReach:

• A warmup network built around positive interactions (opens, replies, marked important, and removed from spam).
• Reputation tracking by provider (Google, Microsoft, and other ESPs)
• Alerts via Slack/webhooks when reputation scores change
• A clear ceiling and structure: up to 100 warming emails per day
• The deliverability toolkit, alongside warmup: domain/inbox health checks (blacklist, SPF, DKIM, DMARC), plus a reputation-tracking dashboard.

Pricing: MailReach is priced per mailbox, and their pricing builder shows a starting point of around $20/month for 1 mailbox (with options to scale mailboxes and add spam test credits), and they also promote an annual discount.

Key Takeaways

Even with the perfect email copy, hyper-targeted lead lists, and segmented campaigns, not every lead will reply or open your email. And if you’re sending at scale, there’s a higher chance your sending reputation will go down.

Email warmup protects your domains and inboxes from these potential adverse effects. To recap, here are the platforms we recommend:

• Instantly: Best for cold email marketing, with premium warmup pools available for free.
• Apollo: Great if you’re looking to focus on prospecting + warmup.
• Boxward and Mailivery: If you want to focus on a few high-performing sending accounts.
• MailReach: Let’s you add unlimited domains to your warmup, but caps warmup volume.