# Warm up a new domain > Build a reputation for a new sending domain step by step, start with your most engaged readers, and pace sends with segments and the hourly limit. Source: https://sendbroadcast.net/university/deliverability/warm-up-a-new-domain A new domain has no history, and mailbox providers treat unknown senders with caution. A sudden burst of thousands of emails from a stranger looks like spam, even when it is not. In this lesson you plan a warm-up: who gets your first emails, how fast to grow, and how to use Broadcast to pace it. ## When you need a warm-up You need one when the domain or the sending account is new to sending, or when you return after a long gap. Common moments: - You move your list to Broadcast and send from a new domain or a new provider account. - You add a new sending subdomain, such as `news.example.com`, for newsletters. - You start sending marketing email from a domain that only ever sent a few personal messages. The reputation that providers build is tied to your domain and to the infrastructure you send from. A new domain starts at zero, whatever your old platform's numbers were. ## Before the first email Warming up a domain with broken authentication wastes the effort. Check these first: 1. SPF, DKIM and DMARC are **Healthy** on **Settings → Email → Domain DNS Health**, and DKIM is aligned with your From domain. Lesson 2 covered this. 2. ESP webhooks are set up, so bounces and complaints suppress addresses at once. 3. Your old platform's hard bounces and complaints are in your suppression list. Mailing addresses that already bounced elsewhere is the fastest way to damage a new domain. 4. On Amazon SES, your account is out of the sandbox. The sandbox allows at most 200 messages in 24 hours. ## Start with the people who want your email Mailbox providers watch what readers do. Opens, clicks and replies tell them the mail is wanted. Deletes without reading and spam reports tell them the opposite. So the first emails should go to the people most likely to engage. In Broadcast, build that audience with a segment. Open **Segments**, click **New Segment**, and start from the **Engaged (30 days)** template: subscribers who opened or clicked an email in the last 30 days. After a few good days, widen it, for example to the last 60 days, then 90. One catch after a move from another platform: opens and clicks from your old platform do not come across. Engagement segments start empty. In that case, build the first audience from what you do have. Your newest subscribers are a good choice, and so are customers who bought recently, if that is in their custom data. ## How fast to grow A schedule that works for most senders: 1. Day 1: send to about 25 to 50 people. 2. Each day after, while things look good, grow the volume by about 25 to 30%. 3. Widen the audience from your most engaged readers toward the rest, step by step. 4. Expect the whole process to take about 4 to 6 weeks. | Day | 1 | 8 | 15 | 22 | 25 | | --- | --- | --- | --- | --- | --- | | Emails | 50 | 238 | 1,137 | 5,421 | 10,000 | An example: a list of 10,000, starting at 50 and growing 25% a day with no pauses. Pauses and stops take most warm-ups to 4 to 6 weeks. Spread each day's sending out instead of sending everything in one burst. It looks more natural to the receiving servers. ## Use the hourly limit to pace sends Broadcast already has the tool for that. Every email server has an **emails per hour** limit, set in **Settings → Email Servers**. A broadcast never sends above it. It sends what fits, waits for room, and continues by itself, in the **Sending** status. So during a warm-up, set the broadcast server's limit low. A limit of 50 per hour turns a send to 400 people into a send spread over about 8 hours. As the warm-up goes on, raise the limit. The lowest value Broadcast accepts is 15. - 400 per hour: 1 hour - 100 per hour: 4 hours - 50 per hour: 8 hours Time to send a broadcast to 400 people at each limit. A lower limit spreads the same send further. On a server that sends only broadcasts, a broadcast can use the full limit. On a server that also sends transactional email and sequences, broadcasts stop at a lower share, so check the numbers the server page shows for your limit. ## Watch the numbers, and stop if they turn After each send, open the broadcasts list and read **Bounce** and **Spam**: - A bounce rate climbing toward 2% means old or bad addresses. Stop widening, and clean the list first. - Any spam complaint rate near 0.1% is a warning. Slow down, and send only to your most engaged readers until it drops. - Low clicks with good delivery can mean placement in spam. Check with a few test addresses of your own at Gmail and Outlook. If something looks wrong, pause the warm-up. Do not push through. A reputation that drops during a warm-up takes much longer to rebuild than the warm-up itself. ## After the warm-up The warm-up ends, but the habits do not. Keep sending at a steady rhythm. Big jumps in volume, such as a sudden send to a long-dormant segment, can look like a new sender again. Keep mailing people who engage, and keep removing people who do not. Lesson 5 covers that. The [warm-up guide](/warm-up-email-domain) has more on schedules. ## What you learned - A new domain or provider account starts with no reputation, and needs a warm-up. - Fix authentication, webhooks and suppressions before the first send. - Start with 25 to 50 engaged readers, then grow about 25 to 30% a day over 4 to 6 weeks. - A low **emails per hour** limit spreads a broadcast over the day. ## Quiz 1. Who should get your first emails from a new domain? - The whole list, so providers see real volume - Subscribers who never opened, to test them - Your most engaged subscribers, such as people who opened in the last 30 days (correct) Engaged readers open and click, which tells mailbox providers your mail is wanted. 2. About how much should daily volume grow during a warm-up, when the numbers look good? - 25 to 30% per day (correct) - Double every day - 5% per week - It does not matter Start with 25 to 50 emails on day one, then add about 25 to 30% per day while bounces and complaints stay low. 3. Which Broadcast setting can spread a broadcast across the day? - Track opens - The email server's emails per hour limit (correct) - The confirmation link expiry A broadcast never sends above the hourly limit. It sends what fits, waits for room, and continues by itself.