List Validation Service FAQs

List validation services are a hot topic among many senders recently. But aside from the information on each service’s individual site, it can be hard to find basic education on their function and purpose.

Before you buy a list validation service, read through these FAQs to gain a better understanding of how and why a validation service might benefit your email program.

What is a list validation service?Generally speaking, list validation services are able to identify email addresses pre-deployment as either valid or invalid. Every service is different, so you will likely find that there are more possible results than just those two, but the idea is that these services help you identify good and bad addresses before sending to them.

Why use this type of service?
List validation services are best used in two scenarios:

  1. To prevent collecting and sending to invalid email addresses that would result in losing an opportunity to connect with a potential customer. Whether email addresses are being collected by a cashier at point of sale or submitted by the customer via an online form, human error is inevitable. List validation services can help cut down on the number of erroneous email addresses.
  2. To prevent hurting your sender reputation. Unknown users, along with spam traps and inactive addresses, are just part of the list hygiene puzzle. The bottom line: the cleaner your list, the better sender reputation you’ll have, resulting in your messages getting delivered into the inbox.

When should you use this type of service?
In my opinion, here’s where you’d get the most bang for your buck:

  1. Real-time validation at point of sale or signup to ensure collection of valid addresses. Note that simple scripts can usually be written into web forms to reject addresses such as [email protected], but list validation services can typically take it a step further and identify things like whether or not an address exists at the written domain before sending.
  2. Batch validation prior to mailing. Even if real-time validation isn’t in place, validation services typically have the option to run a one-off file through validation before mailing so that you still have the opportunity to clean your list before sending.
  3. If you are ever thinking about sending to an old file. If you have a list of email addresses that you haven’t sent to in a while but have reason to send to them, reduce your risk by sending the list through a validation service first.

Do list validation services identify spam traps?
No, not really. Keep in mind that spam traps are accounts that do exist and are deliverable. So, if we are talking about deliverable vs. undeliverable, a list validation service would place them in the “deliverable” bucket based on that criteria. Furthermore, no one has an exhaustive list of spam traps monitored by mailbox providers and blacklists. Spam traps are created for the sole purpose of catching senders who practice poor list hygiene and/or acquisition techniques. Making spam trap addresses public would mean that such senders could still practice these techniques without the consequence of hitting spam traps and, thus, the purpose of spam traps would be completely diminished.

However, most validation services do go a bit beyond classifying addresses as deliverable or undeliverable. For example, they might flag or warn a sender of the following types of addresses:

  1. Role accounts (ex. [email protected], [email protected], etc.)
  2. Typo traps (ex. [email protected])
  3. Other (the service might identify something suspicious about the address, but should give you reasons why)

What you do with these three types of addresses is up to you. Ask a lot of questions around why they are flagged, especially anything that falls into the “other” category, and then make an educated decision around whether or not you should send to them.

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