There’s nothing wrong with having mailing list comprised of hundreds or even thousands of subscribers. However, the large list that you’re so proud of could actually be working against you.
Just like anything else, mailing lists need to be cleaned periodically to remove inactive subscribers, duplicate addresses, ‘role’ accounts such as ‘sales@” or “support@”, invalid addresses and so forth.
Email services are costly, especially if you have a large list. They typically charge by how many subscribers you have so you don’t want to pay for a bunch of inactive subscribers and dead addresses. In addition, having duplicate addresses and addresses that bounce can have a negative impact on your deliverability rates. So it’s important to clean your mailing lists regularly.
There are software programs and web-based services available that can help clean lists, but the jury is still out on how effective they really are. Instead, you can manually clean your list in a weekend or less, depending on the size of your list.
The first step is to remove bounces addresses. Most email service providers these days will have a way for you to view and delete bounce addresses. As you work through these, check the addresses to see if perhaps there is a misspelling. For example, it might say yahoo.cmo instead of yahoo.com. If a subscriber was rushed when they signed up, they may have inadvertently left out a letter or rearranged letters in their email address.
Once you have finished removing bounces. You can go through your list looking for and removing duplicate addresses. Some of the top email service providers will check as they send messages to ensure they are only sending the message once for each address, however, that doesn’t mean the address isn’t in your system more than once – so you’re are being charged for the same address twice.
The final step is to work through your list to delete subscribers who have not read or clicked on any links in a given period of time, let’s say the past year. A lot of these addresses will probably be role addresses that go to a support desk or to unmonitored address that people only check once in a blue moon.
Now that you have a clean list, you should see your deliverability and click through rates improve because the only people left on your list are those who are active and still interested in what you have to say.
If possible, you should plan to clean your list quarterly or at the very least, twice a year.