When it comes to lead generation, your strategy for cold emailing is only as effective as your deliverability. You can have the best marketing team in the world with the most persuasive copy to ever exist, but you won’t close any deals with it sitting in someone’s spam folder.
This is where email warmup tools come into play. Warmup tools are automated systems that know how to slowly and organically build up a reputation for you as a sender. With that reputation in place, you can be confident that your emails are reaching inboxes instead of junk folders.
For lead generation agencies that send a high volume of outreach, choosing the right warmup tool is an absolute necessity. In this article, we’ll rank seven of the best warmup tools and go over the strengths and weaknesses of each one so you can see which will work best for you.
Our number one pick has to be Instantly. What sets this tool apart so much? Well, unlike some of the competition, it doesn’t just feature warmup as a small facet of a bigger product. With Instantly, warmup is treated like the critical component of successful outreach that it is. You get a proprietary network of inboxes that simulate the kind of authentic interactions that boost your reputation quickly.
Here are some of Instantly’s top features:
If you’re a lead gen agency that wants to grow fast but not bother with employing too many tools or dealing with hidden fees, Instantly is right for you.
This is a tool that does exactly what it sounds like it does. If you’re an agency that needs a tool to warm up your inbox but doesn’t come with any add-ons or extra features, this one might be worth your consideration. Warmbox Inbox offers a large network of inboxes that simulate human interaction. This will help by gradually boosting your sender score and keeping your messages from getting caught up in spam filters.
What you won’t get is a full outreach platform like Instantly. But if you already have an existing workflow to cover the rest of your outreach, this is a simple and functional option.
Here are some of the top features you’ll get with Warmup Inbox:
Another popular warmup tool is MailReach. MailReach builds trustworthiness with your domain over time and gives you analytics and domain health tracking. This is really useful for an agency that may not be happy with its deliverability and wants to investigate why things aren’t working as smoothly as they should. MailReach gives you insights that you can take action on in real time.
Here are some of MailReach’s top features:
Any agency that wants to troubleshoot or prioritize long-term email outreach health could benefit from MailReach.
If you have a generous budget and want a product with robust features, Folderly should be on your list to consider. With Folderly, you get a full-service deliverability optimization platform with AI-driven diagnostics and live support. The export support particularly makes it good for agencies that have high-ticket clients or enterprise campaigns.
You’ll also get a range of solutions to fix spam issues. These include checking DNS settings, content scoring, and custom optimization for your entire cold email infrastructure.
Folderly’s top features include:
Folderly is good for an enterprise-focused lead gen agency, or a boutique firm that handles sensitive deliverability issues.
If you want a program known for consistency, Mailwarm is one of those that has been around on the market for a long time . Mailwarm automates warmup using a simple system of sending and replying behaviors that will build your credibility over time.
While Mailwarm isn’t as scalable as others (like Instantly) and doesn’t offer as much data visibility as some of its newer competitors, it can still get the job done, and the learning curve isn’t too intimidating.
Top features for Mailwarm include:
Mailwarm is great for a smaller agency, or even freelancers who are only running a few cold email campaigns at a time.
For a tool that offers a wide range of warmup templates and behaviors ready to be customized, check out Warmbox. Warmbox allows you to tailor almost every step of the process, from open and reply rates to email types and time zones. This can really help an agency mirror a specific campaign style more closely.
Some of Warmbox’s top features are:
Warmbox is good for any agency that wants to have a more granular level of control in how its warmup traffic will behave.
For Gmail users that work with cold outreach, Gmass is probably already familiar. It’s a built in warmup feature for agencies that already use the product. Gmass increases your daily send limits and also opens, replies to, and removes your emails from spam folders to build up trust.
If you’re on a tight budget and don’t want to pay for an additional service, Gmass is easy to install and use.
Some of the top features you’ll find in it are:
For a freelancer or small agency that already uses Gmail for outreach, Gmass may be the most logical option.
It’s easy to be distracted by flashy features and UI designs, but for a lead gen agency, you’ll live or die by inbox placement. Your warmup strategy should include a tool that will support your entire cold email campaign by delivering top-tier warmup and the outreach tools you need.
Instantly is that tool. It goes beyond just warming up inboxes. You can onboard new domains, manage dozens of accounts, and trace your success as it happens with Instantly’s real-time reporting and analytics. Don’t just choose the option that offers email warmup; choose the one that heats up your entire lead pipeline.
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