Email deliverability for ecommerce stores
Where the addresses come from
- Checkout, where the address is captured mid-purchase with no confirmation step and a customer in a hurry.
- Discount popups offering a code, which invite a throwaway address in exchange for the voucher.
- Abandoned cart capture, where the address is taken before the person decided to buy anything.
- Loyalty program sign-ups, usually the cleanest source in a store because the incentive rewards a real address.
Peak season is the worst time to discover a problem
Retail email volume concentrates violently around Black Friday and the weeks before Christmas. A store that sends modestly for ten months and then sends daily for six weeks is a volume spike, and mailbox providers read spikes as suspicious.
Doing that on a list that has not been checked since last year means the accumulated decay arrives at the same moment as your highest-value campaigns and your least forgiving reputation window.
The work belongs in September. Check, warm the volume up gradually through October, and arrive at the peak with a list and a sending pattern that the receivers already recognize.
What the results tend to look like
Consumer-heavy, so Gmail dominates and resolves reasonably well. The difficult share is Yahoo, AOL and the US ISP domains, which accept every probe by policy and cannot be confirmed by anyone. Wholesale and trade customers add a business tail with catch-all domains.
What to do about it
Validate at checkout, not after the sync
That is the capture point and every cleaning pass afterwards is repairing something that could have been caught while the customer was still looking at the field.
Check in September, before the peak build
Arriving at Black Friday with an unchecked list means the decay lands during the least forgiving sending window of the year.
Require confirmation before releasing a discount code
Popup signups are the highest-bounce source in most stores, and confirming before sending the code removes almost all of the junk.
Separate transactional order mail from campaigns
A shipping confirmation should not be filtered because a promotional send damaged the reputation the week before.
Questions people ask
Why do checkout addresses bounce more than signup addresses?
Because there is no confirmation step and the customer is mid-transaction. The order completes whether or not the address was typed correctly, so nothing forces a correction.
When should a store check its list?
Before the peak build rather than during it. September for a Black Friday program, so the list is clean and the volume ramp is gradual.
Are Yahoo customers a problem?
Unverifiable rather than problematic. Yahoo accepts every probe by policy, so those addresses come back unresolved from any honest checker and engagement history is the only signal available.
Related sectors
See the breakdown on your own list
100 free checks a month, no card. Addresses we could not get an answer on come back labeled rather than guessed at, and we do not bill them.