Illingworth says Google to Microsoft replies hit 0.3%
The recipient's email provider sits sixth on a seven item spam list, and it is the one item no records audit fixes.
Richard Illingworth posted a seven point list of why cold email lands in spam, and one item put a number on something most senders never segment by. Google to Google sends get a 4% reply rate, he says. Google to Microsoft gets 0.3%.
That is a claim from one operator, not a published dataset. He does not say how many sends sit behind the two figures, over what period, or in what verticals. Treat it as a directional read from someone who watches inbox placement, not as a benchmark you can quote back to a client.
The rest of the list is standard hygiene
The other six reasons are the familiar ones, which is part of the point. Raw Apollo data comes back 50 to 65% valid, so part of every unvalidated send bounces, the same figure he has used before. Sending from your main company domain means one flag costs you the whole domain. Ten inboxes crammed onto a single domain is a pattern that gets the lot flagged at once. SPF, DKIM, DMARC and MX all have to be correct before the first send, not after. A fresh inbox needs roughly 14 days of warmup before real volume. And a bounce rate over 2% with nobody re-verifying the list keeps compounding.
His own summary points at the cheapest fixes first.
go check your auth records and your bounce rate first.
Why the provider split is different
Every other item on that list is something you control on your side. You can validate the list, split the domains, fix the records, slow the ramp. The recipient provider mix is not a setting. It is a property of the people you decided to contact, and the only lever is which accounts go on the list in the first place.
If the 4% versus 0.3% gap holds anywhere near that size for your sending, it means a list that skews Microsoft is a different campaign from a list that skews Google, even with identical copy and identical infrastructure. Most reporting tools will not show you that split by default, so a campaign can look broken on aggregate reply rate when the real variable is who the mail went to.
The practical move is small. Before you blame copy for a flat campaign, check what share of the list sits behind Microsoft and whether your last two winners happened to be Google heavy. Illingworth's numbers are his own, but the segmentation costs nothing to run on data you already have.
go check your auth records and your bounce rate first.