Lesson 9: Your cold email reputation

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In this lesson, you’ll learn about one of the most important concepts in cold outreach: domain and email reputation. I’ll explain why reputation is essentially your trust score with email providers and why that trust determines whether your emails land in the inbox or spam.

You’ll also learn why pacing your sending, warming up properly, and maintaining strong engagement are critical for long-term deliverability.

By the end, you’ll know how to set up your email accounts for stable, predictable inbox placement – giving you a strong foundation for all your cold outreach campaigns.

In this lesson, you’ll learn:

• How email reputation works like a credit score that you build separately with every major provider – meaning good standing with Google doesn’t automatically protect you with Microsoft, Yahoo, or anyone else
• Why letting a new domain sit unused for a couple of weeks before warming up sets you apart from spammers, and why keeping daily volume under 50 emails per account is backed by real data across 5,600+ active mailboxes
• What actually happens when you rush a two-week warm-up – open rates look promising at first, then collapse by day 45–60 as your thin reputation buckles under the first wave of negative signals
• How the “old school” approach of a two-month warm-up followed by a slow ramp builds a foundation strong enough to absorb spam complaints and low engagement without falling apart – saving you the ongoing cost and operational headache of constantly replacing burned domains

Hi, welcome to this lesson on reputation.

We’ll talk about:

• why it matters, 
• how it’s built, 
• and what practices give you the best chance to land in the inbox.

In the last lesson we talked about warm-up.
Its goal is to build trust.
In cold email, that trust takes the form of your domain and email reputation.

You can think of reputation like a credit score.
Good signals, li ke opens and replies, build it up.
Bad signals, like bounces and spam complaints, burn it down.

But here’s the tricky part.
Your reputation is not global.
It’s built separately with each email service provider.

So you could be doing fine with Google,
but Microsoft might see you differently and push your emails to spam.
That’s why you need to build trust with all major providers:

• Google, 
• Microsoft, 
• Yahoo, 
• and so on.

Now how do you actually do that?
It starts from the very beginning.

Your first impression so to speak.

You have to keep in mind that email providers have one core job:
Keep the inbox spam-free  , scam-free, and relevant.

So your sending behavior can’t look like something a spammer would do.

Spammers usually do this:

• buy a fresh domain, 
• set up email accounts, 
• and start blasting emails right away.

That’s why young domains are often treated as suspicious by filters and blacklists.

To avoid this, you want to let your domain age.
No sending for the first few days, or even a couple of weeks.

This used to be standard practice but got lost when cold email shifted toward horizontal scaling.

Still, if you want to build long-term reputation, letting your domain sit for a couple of weeks is something to strongly consider.

Now back to the spammer.
After buying the domain, they also send large volumes right away.
You can set yourself apart by keeping volumes low and human-like.

That’s why the current best practice is to send up to 50 emails per day from a single account.

Here you can see real data based on over 5 600 mailboxes, active in the last 90 days.

On the X-axis we have daily volume per mailbox; on the Y-axis, the engagement.

Accounts sending 1 to 50 emails had much higher open and reply rates.

Higher volume groups performed worse.

It’s not just the volume per day, but it definitely plays a role.

Next, let’s talk about interactions and engagement.
Spammers typically get poor engagement: low opens, no replies, and lots of spam reports.
They also hit more bounces because their list quality is poor.

This is where warm-up helps.
You send high-quality, low-risk messages to generate positive signals early.
That creates a clear contrast to spammers and scammers.

The so-called best practice today is to do a 2 week warm-up.
That’s fine, but often not enough if you want to keep your domains for longer.

Also, this advice comes typically from lead generation agencies.

They generate leads for their clients, and they need to do it fast.

This is why they are often under pressure to keep warm-up as short as possible.

If you do not have that pressure I would suggest investing into warm-up.

It will be your foundation for long-term sustainable sending.

To illustrate this I want to show you two different scenarios.

Keep in mind that how your domain will perform depends a lot on the engagement you drive.

If you get a lot of spam complaints or bounces early on you may burn through reputation quicker.

So let’s look at Scenario one:

• You warm up for 14 days.
• You build a bit of trust, but your domain is still fairly new.
• You start sending cold emails and at first see 40% to 50% open rates.

But soon, typically within a few weeks, things change.

Negative signals come in: no opens, no replies, maybe even spam complaints.
Because your foundation was weak, your deliverability starts to fall apart fast.

By day 45 to 60, most emails land in spam.
Your email accounts may even start to disconnect much more often.

And worst of all, you might lose high-value opportunities, just because they never saw your message.

Now let’s look at scenario two.

This time, we go the “oldschool” route.

You wait 14 days before doing anything, just to let the domain age.

Already this sets you apart from spammers.

Then you warm up, not for two weeks, but for two full months.
Again, something scammers almost never do.

Once that’s done, you slowly introduce cold emails.
You keep total volume around 50 per day, by balancing warm-up and cold outreach.
For example: 25 cold emails, 25 warm-up emails.

Now your reputation is stronger.
It can handle more stress, like spam reports, low open rates, or a few bad leads.
It won’t break under pressure the way a rushed setup does.

So can you do cold outreach after just 14 days of warm-up?
Yes, but your accounts will burn out faster.

You’ll need to replace email addresses and domains more often,
which costs more and creates more operational work.

What I showed you is how people used to build cold email properly.
And I don’t think that has changed.

Because in the end, reputation = trust.

And trust takes time to build.

Some agencies are already shifting back.
You’ll see 21-day warm-ups, or even longer.

Now, if you’re in a rush and want to get going sooner,
I’ll show you how to start sending quickly,
while being in control of your reputation in the process.

Join me in the next lesson.
I’ll walk you through exactly how to get moving fast while setting things up for long-term success