THE ZB GUARANTEE

Other companies say it, we put it in writing. ZeroBounce, the leader in email validation, makes you the promise of cleaner and safer email lists. We guarantee the following accuracy rates at a minimum:

• 96%+ Accuracy rates on AOL, Yahoo, and office 365 email accounts. This does not include disabled accounts.
• 99% Accuracy rates on everything else.

How the Guarantee works:

If the accuracy rates are below these thresholds, we will refund 5 times the amount for each 1%. Let's say you have a 97% accuracy rate, which is 1% below the guaranteed threshold of (99% Accuracy rates on everything else). We will refund 5 x 1% (or 5%) of your total validation cost for those emails. If your accuracy rate is 2% below the guaranteed threshold, our refund will be of 10% of your costs. If it's 4% below, the refund will be 20%, and so on.

In order to qualify for the guarantee, the following conditions must be met:

• You only email the _valid.csv and remove all toxic and disposable emails.
• You email the list within 72 hours after cleaning.
• Bounces must be invalid emails (Hard Bounces).
• Bounces due to spam content, blacklisted IP's, technical Issues, invalid mail configuration, throttling, etc do not qualify for the guarantee.
• The minimum list size must be 1000 emails.
• This list must be an opt-in list that you collected and not purchased from a 3rd party
• You must provide an export of your full mailing of all emails you sent to and their bounce responses (the actual SMTP Codes and messages of the bounces), not your email sender classifying it as a bounce. ZeroBounce does not guarantee the acceptance of your cleaned list at any ESP provider.

SMTP BOUNCE CODES

SMTP Bounce codes are returned by the different mail servers indicating why they didn't accept the emails that you sent it. It can be for many different reasons, having an email bounce is not always an indicator of an email being invalid. It can be for many other reasons, the most common is that the spam filters identified the message as "Spam Content" and rejected it.

In order to determine why the emails that were sent bounced, it's important to have access to these codes, so you can make adjustments and decisions to remedy the issue.

Below you will find a summary of codes, keep in mind, there are thousands more, depending on the mail server the same codes will have different meanings, these are just a few examples.

Reference: RFC2821

5.X BOUNCE CODES (PERMANENT FAILURES)

4.X BOUNCE CODES (TEMPORARY FAILURES)