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MailCull

MailCull blog: field notes on email deliverability and list quality

2026 9 of 9

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.

September 27, 20266 mindeliverability

You Inherited a Purchased Email List. Now What?

Verification tells you the addresses work. It cannot tell you that you may mail them.

September 24, 20266 minlist-cleaning

Email Verification and GDPR: What Is Lawful When You Clean a List

An email address is personal data. Verifying it is processing. Here is what that means.

September 21, 20266 minlist-hygiene

Stop Bad Email Addresses at the Signup Form

Cleaning is repair. This is prevention, and it costs less.

September 15, 20266 minlist-hygiene

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.

September 12, 20266 minlist-hygiene

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.

September 9, 20266 mindeliverability

The Real Cost of a Dirty Email List (With the Actual Math)

Four costs, three of them invisible. Here is the arithmetic.

September 6, 20266 minlist-cleaning

How to Reduce Your Email Bounce Rate: The Complete 2026 Guide

Bounce rate is a single number with five different causes underneath. Here's how to find yours and fix the right one.

August 13, 20268 minbounce-rate

How Often Should You Clean Your Email List? (Cadence by Sender Type)

Quarterly for most. Monthly for daily senders. Every campaign for cold outreach. Why the math works out that way.

August 4, 20266 minlist-cleaning
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