Your domain's history follows you, but Gmail, Outlook and Yahoo also look at where your email is sent from. When that changes, they re-evaluate you. A sudden full-list blast from a new system looks suspicious; a gradual ramp with strong engagement confirms you're the same trusted sender.
​

Spoks sends through SendGrid, the same sending infrastructure used by platforms like Klaviyo and Shopify, and we keep it warm and well maintained at all times. Every sender on Spoks also passes an automatic quality control before their first send, stricter than any we've seen elsewhere, and you've already passed it. Your warm-up builds on that foundation, it doesn't start from zero.
​

We use a combination of data points from your store to sort your contacts from warmest to coldest. The first segment is your 2 500 warmest contacts, and each segment doubles from there until your full list. Each new campaign goes to the next segment. Never send the same email to more than one segment, the smaller segments are already part of the bigger ones.
​
You don't build these segments and won't find them under Contacts. They appear as recipient options when you choose who a campaign goes to.
​
Write a new email (a different campaign) for each step. Each segment grows to include everyone from the previous one, so the same email should never go to more than one segment.
​

Example of warmup segments:
​
​

About 24 hours after each send, Spoks rates it, and the rating decides your next send size, starting from 2 500:

The wait between sends is enforced, not only advised. The next segment unlocks around 24 hours after your last campaign was sent, counted from the send itself rather than from the calendar day. If your last campaign went out at 2pm, the next one is not available until about 2pm the following day.
​
Until it unlocks, selecting the next warm-up segment on a campaign can show an estimated recipient count of 0 and a prompt to add recipients, even though the segment itself still lists thousands of contacts. That is the wait, not an empty segment and not a broken filter.
​
If more than 24 hours have passed since your last campaign and the next segment is still unavailable, contact support and we can lift it for you.
​

Yes. Choose I'll handle warmup manually on the warm-up task and the limits are removed. Pacing is then up to you, so start with your most engaged contacts, such as past buyers, and build up from there.
​

Pause and hold your current segment if bounces exceed 2%, spam complaints exceed 0.1%, or open rates drop sharply. These are early warnings that you're moving too fast.
​

Warm-up is done once a campaign has gone to the largest segment, your full list. The warm-up segments are only used for the ramp, so they are not part of your normal sending. From then on you choose recipients the usual way: your full list, or any segment you have built under Contacts.
​
The rule about never sending the same email to more than one segment belongs to the ramp, because each warm-up segment already contains the one before it. It is not a limit on sending a later campaign to everyone.
​
Warm-up applies to campaigns. Flows are not part of the ramp, so you can turn them on while you are still warming up. The steady, low-volume sending a flow produces is good for your reputation.