🚨 The Myth of Email Warm Up - A Warning for Cold Outbound

In today's world, where everything moves quickly online, getting your emails directly to your audience is often tricky. This handy guide aims to simplify the complex world of cold email outreach.

It explains why the common belief that you need to find a shortcut to 'warm up' your email mailbox to reach people's inboxes isn't true. We take a closer look at how emails really get delivered, questioning the usual methods and showing the problems and limitations with popular tricks.

As we go through the details of how to warm up your email, how email service providers (like Google) sort emails, and why quick and easy fixes don’t work, we will show you better ways to send emails. These methods are honest, stick to the rules, and adapt to changes in email marketing, ensuring more durable deliverability through the implementation of best practices.

Additionally, we'll help you understand how to reach people's inboxes effectively without using sneaky shortcuts. This way, you can build a good reputation and a genuine connection with your audience.

TL’DR

If you care to get into the weeds on this topic, please read on :) 

The Myth of ‘Fake’ Email Mailbox Warmup

In the field of cold email outreach, the concept of "email mailbox warmup" has become quite popular. This method revolves around sending “pretend” emails - and then programmatically simulating engagement to convey the illusion of genuine interest. 

The ultimate aim? To hoodwink Internet Service Providers (ISPs) into believing that mailboxes and recipients on their network (Gmail, Microsoft, etc.) are engaging with your email messages, thus they must be safe and wanted by recipients generally. Warm up providers would then tell you that this engagement is the primary factor in determining your mailbox's positive sender reputation. With this newly minted (albeit fake) sender reputation, supposedly your emails will now gracefully land in the primary inbox, not the spam folder. However, it isn't really the full story. The concept is quite alluring though. Just click a toggle and your deliverability problems are magically solved!

Think of it as trying to forge a favorable impression under false pretenses. By sending these contrived emails, you aim to establish a façade of trustworthiness and popularity. ISPs, misinterpreting this faux engagement, might conclude, "Ah, this sender is well-liked. Let’s make their emails visible." Yet, really, it's just an act. The problem is, there’s no data to demonstrate that this actually works or that it’s durable and lasting. Moreover, it all hinges on this belief that Google and Microsoft can’t detect fake emails and fake activity.

Google began cracking down on these practices in early 2023. They've explicitly prohibited using Email Warmup services via OAuth/API access, recognizing this manipulation. These measures underscore a crucial reality: genuine rapport with your audience, built on best practices and authentic engagement, is not only more ethical but increasingly necessary as ISPs evolve to counteract deceptive tactics like Email Warmup. This reality check urges a shift away from manipulative strategies towards sustainable, organic methods of email engagement.

Behind the Curtain

The idea of email warmup is all about using artificial engagement to make it look like there's real email activity happening. 

These services (email warmup providers) send fake emails from your account to mailboxes they manage or those owned by their other customers (P2P), including you. This means they're sending emails to your mailbox, engaging with the messages, and then deleting them—an incredible level of access they're granted. They do things automatically to make it seem like a real person is interacting with these emails — for instance: opening them, moving them from the spam folder to the main inbox, and sometimes even replying to them. 

Economics Don’t Make Sense

Not all ‘Warm up’ Providers can be created equal (if they’re going to stay in business, anyway). In looking at the market offerings and pricing, there is a wide range from $79/mo per individual mailbox to $39/mo for an unlimited number of mailboxes. That’s a pretty big gap. Everyday there seems to be a new ‘Cold Email’ SaaS solution hitting the market with their own unlimited warm up service. Color me skeptical. 

Now, determining the actual difference between the high-end and low-end is fairly difficult because these services are not very transparent about how their offerings actually work. Including not providing any real data that their services either work or perform better than an organic ramp up. There’s no Before and After data to substantiate their results. But when you consider the true costs to deploy a warm up service, maintain a quality pool of mailboxes and avoid detection by Google and Microsoft - you aren’t looking at a cheap proposition. So how could unlimited possibly ever work? My take… it can’t. But, let’s examine:

High-end Warm Up Services:

1. Human cultivated pool of mailboxes that are monitored and likely controlled by the Warm Up provider or through partnerships. Using only premium, well aged domains that have true activity from the ISPs native application or web interface.
2. Large network of provider-owned or controlled IPv4 addresses that can be rotated to ensure there is no clear pattern that a specific IP address or class of IP addresses is routinely accessing and performing similar actions on the same mailboxes. A proxy provider could also be considered, however the vast majority block access to SMTP ports and even API endpoints that are used for sending email.
3. Leveraging Generative AI to write truly unique email copy for each warm up email that the platform sends. Ideally mirroring the same type of content that the accounts real cold outreach might include.

On the high-end, deploying this type of solution would have expenses that continue to accumulate as you add more mailboxes. But, when you’re charging per-mailbox, it can work. If you’re not charging per mailbox, it doesn’t add up. You’ll be losing money, unless you’re skipping some or all of these methods.

Low-end, Unlimited Warm Up Services:

1. For the unlimited plans, the P2P approach seems to be the most logical approach. P2P uses the platform's own clients’ connected mailboxes as their “warmup” pool. Meaning, mailboxes that are largely not used by humans and really only exist to deliver cold email on the providers platform – are now being “hijacked” to simulate engagement. I say “hijacked” loosely because most users don’t know that this is happening or that they agreed to allow their mailboxes to be used for this purpose. Your provider sends email to your mailboxes, moves it around, responds and then deletes it. Removing all traces. It’s an extraordinary level of access and risk, since you’re ultimately responsible for your mailboxes activities. But as quality goes, these types of mailboxes are the bottom of the barrel. They’re used only for sending cold outreach and are rarely, if ever, accessed by a human.
2. Bad Actors: With a low barrier of entry (unlimited for $x per month), it seems more than just B2B companies are getting on the bandwagon for warming up mailboxes. There are plenty of horror stories of users happening to catch a glimpse of warm up emails in their mailboxes (usually due to a bounce message or error) that are using domains that contain popular names like ‘Chase’, ‘PayPal’,’ Wells Fargo’. Or in other words, bad actors are warming up mailboxes to engage in phishing attacks – potentially with the help of your mailbox, mind you.
3. When you think of reputation as a measurement of your mailbox's credibility for delivery, you must also consider the reputation of the recipient mailbox. Using cold email mailboxes as recipients to simulate engagement is obviously cheaper, because the provider is just using assets that you (their customer) are bringing to their platform and then sharing it with others. But there is no real quality control, other than perhaps some basics like avoiding using mailboxes that have higher bounce rates or low reply rates and maybe avoiding domains that haven’t reached a certain age. But these mailboxes will have little if any human interactions (like logging in from a browser, mobile app or sending a real message). These mailboxes will typically only be accessed using IMAP and SMTP from a datacenter IPv4 address, which would seem like an easy red flag for Google or Microsoft to spot.
4. Is all the Warm Up sending/receiving activity originating from the same IP address or IP block - over and over again? Maybe. IPv4 addresses are all fully allocated and assigned. There are no new blocks of IPv4 addresses coming to market, ever. Getting access to a block is both expensive and requires documentation for an approved use (ARIN). There are always IPv6 addresses, but it's a similarly challenged proposition. A proxy service would also be difficult for an ‘unlimited’ model, since the proxy cost is based on bandwidth. The more mailboxes that you (the user) have warming up by sending email, the more bandwidth used by the platform and the more your provider will pay each month to their proxy provider. Again, this is if you can find a proxy provider that is willing to open up SMTP ports and to access API endpoints that are known for email delivery. It's very challenging to find a proxy provider to allow this type of usage as it allows bad actors to spoof where email is actually originating from. The provider on the low-end is probably not doing much to prevent detection on an IP-level by Google and Microsoft, because it's expensive. Which again, seems like an easy red flag for Google or Microsoft to detect.

On the high end, the unit economics probably make sense and the overall value provided to the client is probably much greater. On the other hand, at the low end of the spectrum all of these things can’t be true. You either have to give up profitability, give up unlimited mailboxes or simply give up doing it properly – and hope it doesn’t matter. It’s not a profitable model to offer unlimited mailboxes for $39/mo. Really there is no price that makes sense for ‘unlimited’ because the providers costs aren’t fixed and would be largely usage based. 

Over-reliance on email warmup services can lead to a false sense of security in email deliverability. Particularly in cold outreach – where you're reaching out to new contacts – this method can often overshadow the crucial aspects of effective email marketing: crafting relevant content, personalizing messages, and targeting the appropriate audience. 

Furthermore, excessive dependence on these automated services can result in a lack of initiative to genuinely connect with your audience. Notably, industry giants like Google are aware of these tactics and have taken steps to counteract them. Google's updated Acceptable Use Policies now explicitly discourage and ban the use of such artificial methods to manipulate email delivery, and penalties may be applied for violations.

And this highlights a crucial shift — the need for organic, best practice-driven strategies in email marketing, moving away from quick fixes to focus on authentic engagement and deliverability.

Risky Business

Email warmup services, although popular, come with significant risks. When you enlist these services, you're granting them extensive control over your email account, including the ability to send, read, and delete your emails. This opens the door to considerable liability, as I covered above on the ‘low end’ with bad actors.

Businesses often overlook that their email accounts become part of a larger warmup network upon joining these services, potentially compromising security and damaging their online reputation. In other words, your connected mailboxes that you’re using on the warm up service now become part of the warmup pool too. Since most P2P connected mailboxes are used exclusively for cold outreach and rarely, if ever, accessed by actual humans - they’re easy for ISPs to spot. So whether or not an ISP factors in or limits the engagement score impact of a mailbox that appears to be dormant (without any login from a web browser, like Gmail, for example) is unknown. But it is certainly low hanging fruit that they can easily monitor and measure. Which in turn makes the idea of penalizing domains and mailboxes that are sending messages into these identified ‘warmup’ mailboxes very plausible.

Moreover, it's unlikely that internet service providers (ISPs) like Google and Microsoft lack the ability to identify which domains are using warmup services, especially those from low-end/unlimited domain service providers with the least sophisticated approaches. The consequences of being identified for engaging in these artificial warmup methods can be severe, ranging from impaired email delivery to outright blacklisting, which can be catastrophic for a company's digital communication and reputation.

Saturated with Providers

The email marketing landscape has been significantly transformed by the commercialization of email warmup services. The market is now flooded with numerous providers, each promising improved email deliverability. 

However, this proliferation has not gone unnoticed by ISPs, who have become more vigilant. These providers have recognized that email warmup services are often used to game email delivery systems and have subsequently tightened their regulations against such practices. 

As a result, ISPs are now more actively identifying and penalizing accounts that utilize these deceptive warm up strategies, reflecting a broader crackdown on formerly prevalent digital marketing practices.

Common Misconceptions

Spam Detection Algorithms: A prevalent myth in email is the enigma of ISPs like Google and Microsoft's algorithms for email filtering. While the specifics of these algorithms remain largely undisclosed, it's important to understand that email warmup services, which primarily focus on email openings and responses, only address a small fraction of the factors considered by ISPs. This limited scope means marketers may struggle to adapt their strategies effectively to these intricate and largely unknown algorithms.

ISP Detection Abilities: Contrary to popular belief, it is highly unlikely that ISPs aren't increasingly adept at identifying emails sent through warmup services. This misconception undermines the sophisticated measures ISPs have implemented to differentiate between authentic and manufactured email interactions. Given their silent stance on their capabilities, it's improbable that ISPs like Google and Microsoft aren't actively enhancing their systems to discern between genuine and simulated engagements. Especially in the age of AI.

Differences in Email Interactions: Another common misunderstanding is the perception that ISPs cannot distinguish between automated actions (like transferring emails from spam to the inbox) and those performed by actual users. However, ISPs have evolved their detection capabilities, becoming more proficient at identifying the nuances between these interactions. The varied methodologies employed by warmup services are now more easily recognizable by these advanced ISP systems.

Sender Reputation Isn’t Portable: There is also a misconception about the portability of sender reputation across different platforms. It's a mistake to assume that a strong reputation on one platform, like Google, automatically translates to another, such as Microsoft. Each platform independently assesses sender reputation, and a positive standing on one does not guarantee similar results on another. Teams must be cognizant of this to manage their email deliverability strategies effectively.

Misleading Marketing

Email warmup services often tout themselves as the ultimate solution for email delivery, promising outcomes like guaranteed inbox placement or evasion of the promotional tab. Yet, these claims can be misleading, as they don't align with the intricate workings of ISPs' spam filters.

By making promises beyond their capability, warmup services may create a false sense of security, leading businesses to overestimate the effectiveness of these automated methods. This misperception can hinder the development of a more robust, all-encompassing email marketing strategy, as businesses become overly reliant on these services without understanding the complex nature of email deliverability.

In essence, this overreliance on warmup services may prevent businesses from engaging in more effective, genuine outreach practices and adapting to the evolving landscape of email marketing, as dictated by ISPs' constantly updating policies and spam detection technologies.

Organic Ramp Up: The Better, Durable Way

Rather than relying on the fleeting advantages of warm up services, a more enduring strategy for enhancing email reception lies in organic ramp up. This approach entails gradually increasing the volume of sent emails while ensuring that each message is engaging and pertinent to the recipients. It’s also important to not stay at a fixed sending rate over a long period of time, which could easily be spotted as suspect by an ISP. Randomly changing your daily sending volume, per mailbox, by 5-10% up or down is a better approach for appearing human.

It's also helpful to randomly change your daily send volume, per mailbox, to further simulate human behavior. It's an easy red flag for an ISP to see that a mailbox sends the same number of emails each day.

Final Thoughts

While email warmup services might appear as a quick fix to deliverability issues, they are far from a sustainable solution. The focus should be on building a solid foundation of good email practices, understanding the complexity of ISP algorithms, and steering clear of shortcuts that might jeopardize your email reputation. In the end, authenticity and adherence to best practices will always triumph over quick hacks in the realm of email marketing.