What is Email Database Decay and What Do You Do About It

What is Email Database Decay and What Do You Do About It?

Email marketing is, without a doubt, one of the most effective methods out there when it comes to reaching your customers (a whopping 40x more effective than Facebook and Twitter, according to McKinsey).

That’s why email lists are among the most important money-making assets a business can have.
But what many business owners don’t know is that over time, lists lose their marketing effectiveness.


Because of what’s known as email database decay.

This phenomenon will have an effect on your email list no matter what industry you’re in.

So if you’ve noticed the performance of your email campaigns has been declining recently, read this short article l to discover how you can easily get things back on track.

To start with, let’s answer the obvious question:

What Exactly Is Email Database Decay?

In short, email database decay is the deterioration of an email list over time.

This deterioration when email addresses on your list either become unused or invalid.

This isn’t a rare phenomenon, either.

According to a study by HubSpot, email databases decay at a rate of about 22.5% a year.

What Causes Database Decay?

There are a variety of reasons for email database decay happening.

Here are the main ones:

  • People changing job roles. Sometimes, the people subscribing to your list will use their work email rather than their personal one. These addresses are likely to decay at a much faster rate than other emails because of the simple fact that employees are always changing jobs.
  • Changes with email providers. While less likely to happen with large email providers like Gmail, it’s possible that some email providers will change their domain names, merge with other providers, or even shut down, causing the addresses you have in your database to become invalid.
  • Simple inactivity. When email addresses aren’t used for a long period of time, it’s possible they can be deactivated. Some email service providers deactivate accounts that have been dormant for more than six months.

How Does Email Database Decay Affect You?

Unfortunately, email database decay can have some major negative effects on your email marketing campaigns.

These effects include:

  • Increased bounce rate. When you send to invalid or inactive email addresses, these emails will bounce back, increasing your bounce rate (the percentage of emails your campaign couldn’t be delivered to). Having a high bounce rate can damage your sender reputation and result in your future emails being marked as spam.
  • Decreased email deliverability. As the number of invalid and inactive email addresses on your list piles up, your deliverability rate decreases. This is a problem because email service providers use email engagement metrics in order to determine the quality of the emails you send. If your emails have a low engagement rate, ISPs can doom them to the spam folder or block them.
  • Decreased ROI. A decrease in the number of active addresses you have on your list (as well as the resulting effects of your emails being flagged as spam or blocked) means that your email marketing campaigns will have a lower ROI.

What Can I Do to Prevent Email Database Decay?

While database decay can have disastrous effects on any business that uses email marketing, the good thing is that there are things you can do to protect yourself against it.

Let’s go through them one by one:

1. Regularly Clean Your Email Database

One of the easiest and most effective things you can do to protect yourself against the negative effects of email database decay is to regularly clean your email database.

To do this, we recommend that you use an email validation tool, which helps you verify exactly which emails in your database are invalid or inactive and allows you to remove them within seconds.

You can try using our free email verifier.

2. Enable Double Opt-Ins

A double opt-in process requires your subscribers to confirm their email addresses before they are added to your list. By enabling double opt-ins, you help to ensure that their email addresses are accurate and valid.

3. Engage Your Subscribers Often

Regularly engaging with your subscribers helps keep them active and interested in your emails.

It’s important that you regularly engage with them by sending them relevant content that adds value to their lives or by sending them relevant promotions and offers.

For best results when applying these three steps, it’s important that you monitor your email engagement metrics (open rates, click-through rates, and bounce rates) regularly.

This data can help inform you when it’s time to clear out the invalid and inactive emails in your database.


Email database decay can have major negative effects on your business, causing your emails to potentially be marked as spam and decreasing the ROI of your email marketing campaigns.

Unfortunately, there’s no way to avoid this happening, as database decay can occur for a variety of reasons, from job changes to changes with email providers and even simple inactivity.

Fortunately, there are ways you can protect yourself from this phenomenon today so that you won’t feel the negative effects.

These include:

  • Regularly cleaning your email database using an email validation tool.
  • Getting your subscribers to verify their email addresses by enabling double opt-ins.
  • Engaging your subscribers more often with informative and useful content.

If you’ve noticed that database decay is lowering the ROI of your marketing campaigns—or you’re worried about the emails you send being marked by spam—we recommend that you get started removing the invalid and inactive email addresses from your list right now.

Simply click here now to try using our free email verifier.

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