7 Best Cold Email Account Warm Up Services

Upward graph on a laptop showing improved email deliverability from a cold email warm up service.

Starting a cold email campaign with a brand-new domain is like walking into a party where you don’t know anyone and immediately shouting for attention. It’s not going to go over well. Email providers view new accounts with the same skepticism. They need to see a pattern of normal, human-like behavior before they’ll trust you enough to deliver your messages to the inbox. A cold email account warm up service handles this introductory phase for you. It mimics natural email activity, sending and receiving messages from a network of real accounts to build a solid reputation before you ever hit "send" on your first real campaign.

Key Takeaways

Warm-Up Is Your Ticket to the Inbox: Before launching any campaign, use a warm-up service to build a positive sender reputation. This process teaches email providers like Google and Outlook to trust your account, which is the single most important factor in making sure your emails are actually delivered.
Look for Real Networks, Not Quick Fixes: The best warm-up tools use large networks of real, active inboxes to generate authentic engagement. Avoid services that promise instant results or use fake accounts, as they can damage your reputation and get your domain flagged as spam.
Think Maintenance, Not a One-Time Task: A strong sender reputation requires consistent effort. Keep your warm-up service running in the background even after your initial ramp-up period to maintain high deliverability and protect your domain's health for all future campaigns.

What is a Cold Email Warm-Up Service?

Think of a cold email warm-up service as a reputation builder for your email account. When you send emails from a new or inactive account, email providers like Gmail and Outlook are naturally suspicious. If you suddenly blast out hundreds of emails, their algorithms might flag you as a spammer, sending your messages straight to the junk folder. This is where a warm-up service comes in to vouch for you.

These services work by automating interactions that mimic genuine human behavior. They connect your email account to a network of real, safe inboxes and begin sending a low volume of emails. The inboxes in the network then automatically open your emails, mark them as important, and even send replies. This positive engagement tells email providers that you’re a legitimate sender who people want to hear from.

Over a few weeks, the service gradually increases the number of emails sent daily, carefully building a positive sender reputation for your account. A strong reputation is the foundation of any successful cold email campaign, as it’s the single most important factor in achieving high deliverability. By handling this critical warm-up phase for you, these tools ensure your emails have the best possible chance of landing in the primary inbox where they can be seen, read, and acted on.

Why You Need a Warm-Up Service for Your Campaigns

Let’s be real: you can write the most compelling cold email in the world, but it’s completely useless if it lands in the spam folder. This is where a warm-up service becomes your campaign’s most valuable player. When you start sending emails from a new or inactive account, email providers like Google and Microsoft are immediately suspicious. Sending hundreds of emails right away is a huge red flag that makes you look like a spammer.

A warm-up service helps you build a good reputation with these providers. Think of it as making a good first impression. Instead of showing up and shouting, you’re introducing yourself politely and building trust over time. This process is crucial for improving your email deliverability, which is just a way of saying your emails actually make it to someone’s inbox. The service automates a gradual ramp-up of sending activity, mimicking how a real person would use their account.

For cold email campaigns, this isn't just a nice-to-have; it's essential. Your entire strategy depends on getting your message in front of people. By warming up your account, you’re proving to email providers that you’re a legitimate sender. This simple step ensures your carefully crafted messages have a fighting chance to be seen, read, and replied to. Skipping it means risking your domain’s reputation and having all your hard work automatically filtered into spam, where it will never see the light of day.

How Do Email Warm-Up Services Work?

Think of an email warm-up service as a personal trainer for your new email account. When you create a new email address and immediately start sending hundreds of cold emails, providers like Gmail and Outlook see that as a major red flag. Their spam filters are designed to catch this exact behavior. A warm-up service helps you avoid this by making your new account look like it belongs to a real, active person who sends and receives emails naturally.

These services automate a series of actions that mimic human behavior. They connect your account to a network of other real inboxes and begin a slow, steady process of sending and receiving messages. Over time, this activity shows email providers that your account is legitimate and trustworthy. The entire process is designed to build a positive sender reputation, which is the key to getting your emails delivered to the primary inbox instead of the spam folder. It’s a strategic way to lay the groundwork for a successful cold outreach campaign, ensuring your messages actually reach their intended recipients.

They Gradually Increase Your Sending Volume

One of the biggest mistakes you can make with a new email account is going from zero to one hundred overnight. Email warm-up services prevent this by starting small and slowly increasing your sending volume over time. The process typically begins by sending just a handful of emails each day. As your account establishes a positive history of engagement, the service will gradually ramp up the number of emails sent, usually over a period of 45 to 90 days. This methodical approach helps you stay within the sending limits of providers like Gmail and Outlook, proving that you’re a credible sender, not a spammer.

They Automate Email Interactions and Replies

Sending emails is only half the equation. Real email accounts also receive replies and engage in conversations. Warm-up services automate this crucial step by using a network of thousands of real, established inboxes. They send emails from your account to others in the network, and those accounts automatically reply. If one of your warm-up emails accidentally lands in a spam folder, the service will automatically mark it as "not spam" and move it to the primary inbox. This two-way interaction is a powerful signal to email providers that your account is engaged in legitimate conversations, which significantly strengthens its reputation.

They Build Your Reputation with Email Providers

Ultimately, every action a warm-up service takes is designed to build a positive sender reputation. Think of your sender reputation as a credit score for your email account. A high score tells email providers that you are a trustworthy source, making them more likely to deliver your messages directly to the inbox. By gradually increasing your sending volume and automating realistic interactions, the service systematically builds this trust. This foundational work is what separates a successful campaign that lands in the inbox from one that gets lost in the spam folder, making it an essential first step before launching any large-scale email outreach.

The Best Cold Email Warm-Up Services

Choosing the right warm-up service can feel like a big decision, but it really comes down to your specific needs—like your sending volume, budget, and how much technical detail you want to manage. Think of these tools as partners in your outreach efforts. A good warm-up service works quietly in the background, building your sender reputation so your messages have the best chance of landing in the primary inbox. The goal is to find a service that aligns with your outreach strategy, whether you're a solo founder sending a few hundred emails a week or a large team managing multiple high-volume campaigns.

The services we'll cover range from simple, set-it-and-forget-it tools to comprehensive platforms that offer deep deliverability analytics. Some use massive networks of real users to create authentic engagement, while others leverage AI to craft unique conversations. There isn't a single "best" option for everyone, which is why understanding the differences is so important. We'll look at what makes each one unique, so you can find the perfect fit for your campaigns without getting lost in technical jargon. Let's get into the top contenders.

ScaledMail - Dedicated Infrastructure for High-Volume Campaigns

While most warm-up tools focus solely on preparing your email account, ScaledMail takes a more comprehensive approach by providing the entire dedicated infrastructure you need for high-volume outreach. Think of it this way: a warm-up service gets your car ready for a road trip, but ScaledMail gives you a high-performance engine built for the entire journey. It’s designed for businesses that are serious about scaling their cold email efforts without compromising deliverability. By combining warm-up processes with a custom-built sending system, you can maintain a pristine sender reputation even when sending thousands of emails. If your goal is to run large-scale campaigns efficiently, exploring a dedicated infrastructure is the logical next step.

TrulyInbox - Unlimited Account Connections

TrulyInbox is a standout favorite for its simplicity and powerful core features. What really sets it apart is its generous account policy. As one review of warm-up services notes, TrulyInbox is "praised for being simple, good at its main job, and uniquely allows you to connect an unlimited number of email accounts without extra fees, even on its basic plan.” This is a game-changer for agencies or marketing teams managing multiple domains and client campaigns. Instead of paying per seat or per connected inbox, you can warm up as many accounts as you need under one plan. This makes it an incredibly cost-effective and scalable solution for anyone juggling more than a few email addresses.

Warmup Inbox - Network of 30,000+ Real Accounts

The strength of any warm-up service lies in its network, and Warmup Inbox boasts an impressive one. It uses a network of over 30,000 real accounts to generate authentic engagement for your inbox. A larger, more diverse network means your warm-up emails are interacting with a wide variety of genuine accounts, which looks great to email service providers like Google and Microsoft. Warmup Inbox also allows you to focus your warm-up activities on specific providers and offers conversations in five different languages, adding another layer of authenticity to the process. This is a solid choice if you’re looking for a tool with a robust and realistic network to build a strong sender score.

Lemwarm - AI-Powered with a 10,000 Real Email Network

If you're looking for a more advanced, AI-driven approach, Lemwarm is an excellent option. It leverages a network of 10,000 real email accounts from users in over 100 countries to create highly personalized warm-up sequences. The AI helps craft more realistic and varied email exchanges, moving beyond simple, repetitive messages. This intelligent approach helps your account build a more natural sending pattern, which is crucial for establishing trust with email providers. Lemwarm also includes features for detecting deliverability threats and provides clear monitoring, making it easy to track your progress and ensure your reputation is on the right track.

Mailwarm - Simple Setup with Content Personalization

Sometimes, you just need a tool that’s straightforward and effective, and that’s where Mailwarm shines. It’s known for its incredibly simple setup process, allowing you to get your warm-up sequence running in just a few minutes. But don't let its simplicity fool you—it’s still packed with useful features. Mailwarm focuses on the fundamentals, like verifying email addresses and personalizing content to ensure the interactions look as human as possible. It’s a great starting point for individuals or small teams who want a reliable, no-fuss solution to get their inboxes ready for outreach without a steep learning curve.

Folderly - Comprehensive Deliverability Analysis

Folderly goes beyond basic warm-up and positions itself as a complete email deliverability platform. If you’ve ever wondered why your emails are going to spam, this tool is for you. As one analysis points out, "Folderly is more than just warm-up; it's a full email deliverability service. It tells you why emails go to spam, checks your domain, and analyzes email content.” It provides in-depth diagnostics on your domain health, DNS records, and email copy, giving you actionable steps to fix any issues. This makes it an ideal choice for marketers who need deep insights and want to take a proactive, data-driven approach to managing their email deliverability for the long term.

Other Warm-Up Services Worth a Look

The market for warm-up tools is always growing, and there are many other great options out there. If you’re still exploring, you might want to check out a few other services that users frequently discuss. Based on community feedback, other popular tools include AutoWarmer by QuickMail, Warmbox, GMass, and MailShake’s Warm Up Your Email. Each has its own unique features and pricing models, so it’s worth doing a little extra research if you have a specific need that hasn’t been met by the tools above. Taking the time to compare a few more options can help you find the absolute best fit for your outreach strategy.

What to Look for in a Warm-Up Service

Choosing an email warm-up service can feel overwhelming, but a few key features separate the great from the good. When you're sending high-volume campaigns, you can't afford to guess. Look for a service that offers transparency, robust features, and real results. Here are the non-negotiables to look for when you're vetting your options.

Real User Networks vs. Fake Inboxes

The most critical feature of any warm-up service is the network it uses. You want a service that engages with a network of real, active user inboxes. Why? Because email service providers like Google and Microsoft are incredibly smart; they can easily spot automated interactions with fake or dormant accounts. When your warm-up emails are opened, replied to, and marked as important by genuine people, it sends a powerful signal that you're a legitimate sender. This positive engagement is what builds a strong sender reputation. Services that rely on fake inboxes might offer a temporary illusion of activity, but they won't build the lasting trust you need for successful long-term campaigns.

Reputation Monitoring and Analytics

A warm-up service should do more than just send emails on your behalf—it should give you insight into how your reputation is progressing. Look for tools that provide clear analytics and a reputation score. This data is your window into how email providers see your domain. The best services will monitor your deliverability in real-time and offer actionable suggestions for improvement. For example, they might flag if you're listed on a blocklist or if your authentication records aren't set up correctly. This kind of reputation monitoring allows you to fix problems before they derail your entire outreach effort, turning the warm-up process from a black box into a transparent, data-driven strategy.

AI-Driven Strategies

The days of sending generic, repetitive warm-up emails are over. Modern services now use AI to make the warm-up process more effective and human-like. An AI-driven tool can create personalized warm-up strategies, generating unique email content and varying sending schedules to mimic natural user behavior. Instead of sending the same "hello" message over and over, the AI can craft diverse messages that are more likely to get positive engagement. This intelligent approach helps you avoid spam filters that are trained to detect robotic, predictable patterns. Using AI in your email strategy ensures your warm-up is as sophisticated as the algorithms you're trying to impress.

Integrations and Ease of Use

Your warm-up tool should make your life easier, not more complicated. A user-friendly interface that is simple to set up is essential. You should be able to connect your email accounts in a few clicks and let the service handle the rest. Also, consider how the tool integrates with your existing workflow. Can it connect with different email providers, from Google Workspace to Microsoft 365? For agencies or businesses managing multiple domains, look for services that allow you to connect an unlimited number of email accounts without charging extra per seat. This flexibility is key to scaling your outreach without scaling your costs. At ScaledMail, we believe in straightforward pricing that supports your growth.

Domain and IP Health Checks

Finally, a comprehensive warm-up service should act as a health monitor for your entire sending infrastructure. This means going beyond email interactions to perform regular domain and IP health checks. These diagnostics can identify underlying technical issues that might be hurting your deliverability. For instance, the service should check if your domain or IP has been placed on any industry blocklists. It should also analyze your domain's health to ensure your DNS records are configured correctly. Getting these insights is crucial for troubleshooting. If your emails are landing in spam, a domain health check can often tell you exactly why, allowing you to fix the root cause and protect your sender reputation for the long haul.

How Long Does Email Warm-Up Take?

If you’re looking for a quick, one-size-fits-all answer, you won’t find one here. The truth is, the time it takes to properly warm up an email account depends on several factors, primarily the age of your domain and email address. Think of it like building credit—it doesn’t happen overnight. Patience is your best friend in this process, and rushing it is the fastest way to get your messages sent straight to the spam folder.

For a brand new email account on a fresh domain, you should set aside 45 to 90 days for the initial warm-up phase. This might sound like a long time, but it’s crucial for building a positive sender reputation from the ground up. During this period, a warm-up service will slowly increase your sending volume and generate positive interactions, proving to email providers like Google and Outlook that you’re a legitimate sender, not a spammer.

But the work doesn’t stop after three months. Email warm-up isn’t a one-time task; it’s an ongoing maintenance activity. To protect your deliverability for the long haul, you need to keep the warm-up process running in the background continuously. This consistent, positive activity keeps your reputation strong and signals to providers that your account remains in good standing. Skipping this step is like stopping your car's oil changes—things might seem fine for a while, but you're risking serious problems down the road.

Common Myths About Warm-Up Services

If you’ve spent any time researching cold email, you’ve likely come across some conflicting opinions about warm-up services. It’s easy to get tangled in the debates and wonder what’s true. Let’s clear the air and tackle some of the most common myths head-on so you can make an informed decision for your campaigns.

Myth #1: "Warm-up services are a scam."

This is a big one, and it’s understandable why some people are skeptical. The idea of an automated tool sending emails on your behalf can sound a bit shady. Many worry that email providers like Gmail can easily spot these automated interactions and that the whole thing is just smoke and mirrors.

However, reputable warm-up services are far from being a scam. They are sophisticated tools designed to solve a real problem: building a positive sender reputation. High-quality services use a network of thousands of real, established inboxes, not fake accounts. They automate realistic interactions—like opens, replies, and marking emails as important—to show inbox providers that you’re a trustworthy sender. It’s not about tricking the system; it’s about demonstrating legitimate behavior before you start your outreach.

Myth #2: "Email providers will detect and penalize you."

The fear of being blacklisted is real. Nobody wants to invest time and energy into a strategy only to have their domain penalized and all their emails land in spam. This myth suggests that using a warm-up tool is a risky gamble that could do more harm than good.

In reality, the opposite is true when you use a quality service. The entire purpose of warming up an account is to avoid penalties. Sending a large volume of emails from a new or cold account is a massive red flag for spam filters. A gradual warm-up process builds trust with providers like Outlook and Gmail. By generating positive engagement signals, you’re essentially telling their algorithms, "Hey, I'm a legitimate sender who people want to hear from." This proactive approach is much safer than jumping straight into cold outreach and hoping for the best.

Myth #3: "They cost more than they're worth."

With so many tools in a marketer’s tech stack, adding another monthly subscription can feel like a stretch. It’s easy to look at the price and wonder if the investment will actually pay off, especially when the results aren't as immediately visible as something like ad clicks.

Think of it this way: what is the cost of your emails never reaching their destination? If your deliverability is poor, every single email you send is a wasted effort. A warm-up service is an investment in ensuring your message actually gets seen. The cost of a tool is often minimal compared to the potential revenue from just one or two deals closed from a successful campaign. When you consider the ROI, ensuring your emails land in the primary inbox makes the cost of a warm-up service a smart and necessary business expense.

Are There Any Downsides to Using a Warm-Up Service?

While warm-up services are a fantastic tool for your cold email strategy, it’s smart to go in with a clear understanding of the potential challenges. Think of it less as a list of "cons" and more as a set of factors to be aware of so you can choose the right service and set realistic expectations. When you know what to look out for, you can sidestep common pitfalls and make sure your investment truly pays off. Being a savvy marketer means looking at any tool from all angles, and warm-up services are no exception.

The main things to consider are the sophistication of email providers, the cost of the service, and the time you'll need to commit to the process. None of these are deal-breakers, but they are important variables in your overall outreach strategy. Being prepared for them will help you integrate a warm-up service smoothly and effectively, ensuring your emails land where they belong: in the inbox. Ultimately, understanding these aspects will help you build a more resilient and successful email program from the ground up.

The Risk of Detection by Email Providers

Email service providers like Google and Microsoft are constantly getting better at spotting artificial activity. If you use a low-quality warm-up tool that relies on a network of fake or inactive accounts, you could do more harm than good. These providers can recognize robotic, non-human patterns, and as one expert notes, the worst-case scenario is that using a poor service gets all of your emails marked as spam. This is the exact opposite of what you want. To avoid this, it's crucial to choose a service that uses a large, diverse network of real, active user accounts to generate engagement that looks completely natural.

The Cost and Budget

Email warm-up services are an ongoing operational expense, and the costs can vary quite a bit. Some basic plans start around $15 to $25 per month for a single email account, which is great for getting started. However, more advanced services or plans for multiple accounts can run into hundreds of dollars per month. Instead of viewing this as just another cost, think of it as an investment in your email deliverability. A damaged sender reputation can cost you far more in lost leads and opportunities than the monthly fee for a quality warm-up tool. Weigh the price against the potential return on investment from your campaigns landing in the primary inbox.

The Need for Ongoing Maintenance

Warming up an email account isn't a one-time task you can check off your list. It’s an ongoing process. To maintain a strong sender reputation, you need to keep the warm-up process running continuously, even after your initial ramp-up period. As Warmup Inbox points out, "you should keep your email account warm all the time to maintain a good reputation." This means you'll need to monitor your account's health and ensure the service is working alongside your live campaigns. It requires a long-term commitment, but this consistent effort is what keeps your domain trusted by email providers and ensures your messages continue to get delivered.

How to Choose the Right Warm-Up Service

With so many warm-up tools on the market, picking the right one can feel like a chore. The best service for you depends entirely on the scale of your outreach, your budget, and the features you actually need. Breaking it down into a few key areas will help you make a clear-headed decision.

Define Your Needs and Goals

Start by asking yourself what you need the service to accomplish. Are you warming up a single new email account for a small campaign, or are you managing a dozen domains for high-volume outreach? A simple service that just automates sending and replies might be enough for smaller operations. However, if you’re serious about scaling, you’ll want a tool with more advanced features. Look for services that offer detailed analytics, monitor your domain health, and check your IP address reputation to give you a complete picture of your email deliverability.

Compare Pricing and Value

Budget is always a factor, and warm-up service prices can range from about $15 per month for a single account to hundreds for a comprehensive package. Instead of just looking for the cheapest option, think in terms of value. A slightly more expensive service that uses a network of real, high-reputation inboxes is a much better investment than a cheap tool that uses fake accounts and puts your domain at risk. The goal is to protect your sending reputation for the long term, and paying a little more for a reliable service is often worth it.

Check for Real User Networks and Reviews

The effectiveness of a warm-up service hinges on the quality of its email network. Does it use real, active inboxes from users around the world, or is it a closed system of simulated accounts? A network of real users provides the kind of natural engagement that email providers like to see. To verify a service's quality, look for unbiased reviews and recommendations from other users. Go beyond the testimonials on the company’s website and check out discussions on platforms like Reddit or G2 to get honest feedback from people who have actually used the tool.

Evaluate Integrations and Ease of Use

Finally, consider how the tool will fit into your daily workflow. A good warm-up service should be easy to set up and integrate seamlessly with your email provider, whether you use Google Workspace, Outlook, or another platform. The dashboard should be intuitive, allowing you to quickly check the status of your warm-up, view reports, and identify any issues without a steep learning curve. If a tool is complicated or difficult to manage, you’re less likely to use it consistently, which defeats the whole purpose.

Frequently Asked Questions

Can I just warm up my email account manually? You certainly can, but it's a significant time commitment. To do it effectively, you'd need to send emails to a network of friends and colleagues every day, ask them to open, reply, and mark your messages as important, and then gradually increase the volume. A warm-up service simply automates this entire process at a scale that's nearly impossible to replicate by hand, ensuring consistent and positive interactions that build your reputation efficiently.

Is email warm-up a one-time setup, or do I need to keep it running? Think of it as ongoing maintenance rather than a one-time fix. The initial 45 to 90-day period is for building your reputation from scratch, but you should keep the service running in the background even after you start your campaigns. This continuous, low-level activity maintains the positive signals that email providers look for, protecting your deliverability and ensuring your account stays in good standing for the long haul.

Will a warm-up service guarantee my emails land in the inbox? A warm-up service is a crucial first step, but it's not a magic bullet. It builds a strong sender reputation, which is the foundation of good deliverability. However, other factors like your email list quality, message content, and sending volume also play a huge role. Using a warm-up service gives your emails the best possible chance of reaching the inbox, but you still need to follow best practices for the rest of your campaign.

How do I know if the warm-up process is actually working? A good warm-up service will provide you with clear analytics and reporting. You should be able to track your sender reputation score, see how many of your warm-up emails are being delivered and opened, and monitor for any potential issues, like being placed on a blocklist. This data gives you a transparent view of your account's health and shows you the direct impact of the warm-up activities.

What's the biggest mistake people make when warming up an email account? The most common mistake is impatience. Rushing the process by sending too many emails too soon is the fastest way to get flagged as a spammer. The warm-up period is designed to be slow and gradual for a reason—it mimics natural human behavior. Trust the process, give it the recommended 45 to 90 days, and don't start your large-scale campaigns until your sender reputation is firmly established.