What email warm up is and can you skip it
Warm up is the practice of raising a new sender's volume gradually so receiving mail servers build a record of it before it sends at scale. You cannot skip the process itself, but you can skip the waiting by using a sender that somebody else has already warmed.
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Warm up is the step that turns a two hour setup into a month, and it is the reason most people who want to send bulk email this week end up sending it next month. It is also widely misunderstood as an optional best practice, which it is not.
What is warming up actually doing?
It is building a track record. A sender nobody has seen before has no history, and receiving mail servers treat an unknown sender pushing large volume with suspicion by default.
Sending a small amount, then slightly more, then more again gives those servers a pattern to judge. The pattern is the point; the schedule is just how you produce one.
How long does a real warm up take?
Two to four weeks for a normal sender, and longer if the early results are poor. The schedule usually starts at a few dozen messages a day and roughly doubles each week until it reaches the volume you actually wanted.
Nothing about that can be hurried from your side. The clock belongs to the receiving servers, not to you, which is why a warm up that is rushed simply restarts.
Can you skip warming up?
Not as a process, and anybody who tells you otherwise is describing a shortcut that fails. What you can skip is doing it yourself.
If the sender you use has already been warmed by somebody else, the history exists before you arrive and there is nothing to wait for. That is how PhantomFox works: the senders are pre warmed before you touch them, so the first campaign sends at the rate the hundredth does, with no domain, no DNS record and no warm up period of your own.
| Week | Doing your own warm up | On a sender already warm |
|---|---|---|
| Week one | a few dozen messages a day | full volume, real campaign |
| Week two | a few hundred a day, watched | second campaign, results read |
| Week three | low thousands, still cautious | scaled on what worked |
| Week four | first real campaign | a month of sending already done |
| If it goes badly | start again on a new domain | that one send |
What do warm up tools actually do?
Most of them arrange for a network of mailboxes to exchange messages with your new sender and mark them as wanted. It produces a pattern, and it produces a pattern that does not resemble a real campaign.
They also take just as long. If the aim is to send something this week, a warm up tool is not a solution to your problem, it is the same problem with a subscription attached.
Does skipping the wait change what you should send?
No. The message still has to be worth reading, the list still has to be one you gathered rather than bought, and a bad offer is still a bad offer at any temperature.
What changes is the cost of finding out. The unsubscribes and the spam reports land on our sending infrastructure rather than on an address of yours, so the first campaign is an experiment instead of a commitment. The route is on how it works and the deadline case is on five minute sending for a deadline today.
Read what DKIM, SPF and DMARC are for next for the records warm up is usually paired with, and why emails go to spam for what happens when neither is in place. The full list is on the answers hub.