MailCull blog: field notes on email deliverability and list quality
What to Actually Do With Risky and Unknown Verification Results
Two of the four statuses decide themselves. These are the two that need you.
Email Verification for Agencies Managing Client Lists
You inherit the list and you inherit the blame. Audit before you send.
Nine Email Data Myths That Cost People Money
Nine things people believe about email data that quietly cost them money.
How Ecommerce Brands Lose Revenue to Invalid Email Addresses
The typo at checkout does not just cost you a subscriber. It costs you the order confirmation.
Double Opt-In vs Single Opt-In: The Honest Trade-Off
You lose signups. You gain a list where every address is proven. Here is the maths.
Re-Engagement Campaigns: Winning Back Inactive Subscribers Without Wrecking Deliverability
You are about to mail the riskiest segment you own. Do it in this order.
You Inherited a Purchased Email List. Now What?
Verification tells you the addresses work. It cannot tell you that you may mail them.
Email List Decay: How Fast Your List Rots and What to Do About It
Roughly 2% a month, but the range is wide and the drivers are predictable.
Bulk Sender Requirements in 2026: What Gmail, Yahoo and Microsoft Now Enforce
The 0.3% spam ceiling is the rule everyone quotes. The list-hygiene requirement is the one that catches people.
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