Illingworth says campaigns held with almost no warmup
One operator, no send volumes posted, and he says he is still testing.
Richard Illingworth says his team has been running live campaigns with almost no warmup at all, and that most of them held their deliverability anyway. He posted it as a direct answer to the standard advice that you have to warm inboxes for three weeks before you send. His verdict on that rule is that warmup is massively oversold.
The argument underneath it is about where placement actually comes from. Illingworth's position is that warming an inbox does not purchase anything that lasts, and that what you do once the campaign is live is what decides the outcome. His two levers are keeping daily volume per inbox low and keeping domains genuinely clean. He is not saying skip preparation entirely. He says prep still matters, just not for three full weeks.
What he actually posted
No send volumes, no inbox counts, no inbox placement numbers and no timeframe. He says most campaigns held, which leaves some that did not, and he does not say how many or what happened to them. He also put a caveat on the end of his own post that most people making this argument would have left off.
For people sending
This is one operator's in-progress test, not a dataset, and he labels it that way himself. The practical read is narrower than "stop warming". If your current ramp is three weeks of warmup followed by a hard jump to full daily volume, the claim being made here is that the ramp is doing less work than the ongoing sending behaviour, and that a sharp post-warmup volume spike on a clean domain is the part that hurts you. That is testable on a small slice of a fleet without betting anything you cannot replace.
The risk of taking this literally across every domain you own is obvious. Warmup is cheap and mostly automated, the downside of under-warming is a burned domain and an inbox pool you have to rebuild, and nobody in this thread posted a before-and-after placement figure to price that trade. If you run client sending, the cost of being wrong lands on someone else's pipeline.
What would make this worth acting on is the follow-up. Illingworth says he is still actively testing, so the numbers that matter, how many inboxes, at what daily volume, and what share of sends landed in the primary inbox over how long, have not been posted yet. Until they are, treat it as a reason to run your own ramp test on a few domains rather than a reason to change the default for all of them.
a warmup doesn't buy you a permanent free pass.
we're still actively testing this... but early signs are promising.