Start sending from a new custom domain without landing in spam.

When you start sending from a custom domain, Gmail, Outlook, and other mailbox providers have never seen mail from it. They don't know yet whether you're a real business or a spammer, so they watch closely. A new domain that suddenly sends thousands of emails looks a lot like spam, and providers are more likely to put that mail in spam folders, or slow it down.

Warming up means starting small and sending a little more each day, so providers learn that people want your email. It takes about a month if you send most days. Once you're comfortably sending to your whole list, you're warm.

You don't need to warm up if you send from Quotient's shared domain (send.quotientemail.ai). It's already warm.

How much to send each day

Here's what we recommend for a domain's first month, counting from the day it was verified. After the first week, it grows by half again each day.

Day	Most emails to send that day
1	150
2	250
3	400
4	700
5	1,000
6	1,500
7	2,000
8	3,000
9	4,500
10	6,750

Keep growing by half again each day until you reach your normal list size. There's no need to go further than that. If you usually send to 5,000 people, you're warm once you're comfortably sending 5,000.

These numbers assume you send most days. You don't have to, but don't jump ahead when you skip days: if you sent 400 emails last week, aim for about 700 this time, not your whole list. What counts is how much mail the domain has actually sent, not just how old it is.

Who to send to first

Start with the people most likely to open your email, because opens and clicks are what convince mailbox providers you're legitimate. Good first audiences are:

• People who signed up or bought from you recently
• People who opened or clicked your emails on another platform in the last 30 days
• Your customers, before people who've never bought anything

Leave people you haven't heard from in months until the end of warm-up. They're the most likely to ignore your email or mark it as spam.

What Quotient shows you

For a domain's first 30 days, Quotient warns you when a broadcast would go to more people than we recommend sending that day. You'll see the warning on the broadcast's Details tab, and again when you launch or schedule it. The warning says which day of warm-up the domain is on and how many people the broadcast would reach. It's a recommendation: you can still launch the broadcast.

If you need to reach more people than that, split your audience into smaller lists or segments and send them on different days.

Signs to slow down

Check your broadcast's analytics a day or so after each send, once delivery has settled. Hold your volume where it is for a few days if you see:

• Delivery rate below about 96%
• Spam complaints above about 0.08%, or roughly one in every 1,250 emails

A low delivery rate often means your list has old or mistyped addresses that bounce. Clean it up before you send more. See Suppression & Bounce for how Quotient handles addresses that bounce.