Email tumbling is a simple way to filter incoming emails, by using variations of a Gmail address.
To tumble an email, users just need to insert a "+" and their tumble text at the end of the local part of their email address (the bit before the @).
Here's an example:
janedoe@gmail.com is the root email address.
janedoe+shopping@gmail.com is the tumbled email address.
If you use a Gmail account you'll have filter options. Email tumbling lets users set up filters to move emails around, auto-archive, forward, delete etc. So when Jane buys online Gmail will deliver her shopping emails into a folder automatically, provided she sets a filter up based on her tumbled address (janedoe+shopping@gmail.com).
When we clean email address lists we flag emails that are bad or might be connected to fraud.
Email Tumbling isn't a disposable address. It isn't necessarily undeliverable, or a spam trap either.
If your list contains a growing number of tumbled email addresses, you should keep an eye on them and check to see if there's a pattern. Maybe your tumbled emails are connected to bad transactions that trigger chargebacks. Or maybe their open rates are great and they're your most engaged audience.
If you are not using a proper opt-in process, look out. Tumblers are used to filter and report spam. For example if Jane uses janedoe+spam@gmail.com she can monitor who is using her email address to send stuff she didn't want to receive. Then it's just a quick tap on the spam button to report you for sending her something she didn't ask for.
Learn about why email verification is essential for your business
Email tumbling lets people use multiple email addresses quickly, without having to set up different email accounts. It's a real time saver and if you are online all day trying to get accounts open with fraudulent addresses and stolen credit cards, time is a big issue. This opportunity for fraud is a real concern for online traders - how do you distinguish between Jane Doe+christmas and fraudster+stolencard?
Apart from setting tumbled addresses to one side and watching results, there isn't a lot marketers can do. On the optimistic side, honest email tumblers could give you an opportunity to engage more effectively, as they will be reading your emails if they are genuinely interested.
Read here for explanations of email marketing terms