AWeber lists are usually newsletter subscribers accumulated over many years, sorted by the form that captured them. Exports from long-running accounts carry addresses on domains that stopped existing during the transition away from dial-up.
Getting the addresses out of AWeber
Subscribers, apply a filter, then Export. AWeber emails the CSV.
Before a migration and before returning to a list that has been dormant. Idle time is when decay happens invisibly, and the first broadcast back is where all of it arrives at once.
What AWeber does with the file you bring back
The import rules decide what a re-import actually changes, which is worth knowing before you upload.
The short version
- AWeber matches on email and updates the existing subscriber.
- Unsubscribed and undeliverable addresses are not re-added by an import.
- Custom fields import alongside the address.
- AWeber may review a large import from a new account before releasing it, which is a reasonable protection and worth expecting.
The mistake to avoid
Some addresses come back unresolved, and that is a fact about the receiving server rather than a gap in the check. We label those and never bill for them. What that means, and why roughly 28% of business addresses land there, is set out on our page about catch-all domains.
Upgrades happen by themselves and downgrades don't
Picture a gardening newsletter with 40,000 subscribers that hasn't mailed in eighteen months. You move it to AWeber, the import clears, and your plan steps up to the tier that fits 40,000. AWeber's pricing FAQ is plain about this part: when your subscriber count passes the plan limit, the account is upgraded automatically.
Then the first broadcast goes out and 5,200 addresses come back undeliverable. Your real audience is 34,800, and you're still paying for the bigger tier, because the same FAQ says downgrades aren't automatic and you have to contact their Customer Solutions team to be moved down. Had you checked the file first, the 5,200 would never have been imported, and 1,900 of them sit on domains that no longer resolve, which is the cheapest failure there is to catch. A 50,000 pack with us is $89 and the leftover credits don't expire.
One reader on two lists is two subscribers
AWeber's help page on duplicate subscribers says each list operates independently, so a person who joins a second list in the same account is counted again. If your newsletter holds 24,000 people and your customers list holds 7,000, with 4,500 on both, the figure to look at is 31,000 and not 26,500. Compare the total on your billing page with a deduplicated export and you'll see which way your account is being counted.
Unsubscribes work the other way. Their documentation states that unsubscribed addresses don't count toward billing, so there's no money reason to delete them, and a good reason not to: deleting removes the record that the person opted out. When you're tempted to tidy up, leave the unsubscribes alone and put the effort into merging overlapping lists into one list with tags.
Questions people ask
Why do old newsletter lists bounce so heavily?
Because addresses decay. ISP mailboxes die with the broadband contract, free webmail accounts are abandoned, and work addresses disappear when people change jobs. A ten-year-old list is mostly history.
Should I verify before migrating to AWeber?
Yes. The first broadcast on a new platform is the worst moment to discover a list's real condition, because you have no sending history there to absorb it.
What about addresses on domains that no longer exist?
Those fail at the DNS stage, before any mailbox check, and we mark them undeliverable with confidence. On a long-running list they are a meaningful share.