Why you should warm up a new sender domain
In short: Warming up a new or rarely used sender domain means sending small volumes to your most engaged contacts first and increasing the volume gradually, so mailbox providers learn to trust the domain. If you skip it, your emails can be rejected, quarantined, or marked as spam, your engagement and ROI will drop, and your domain can be blacklisted. Authenticate the domain with SPF, DKIM, and DMARC before your first send.
Marketers often use a new sender domain under the following circumstances:
• They purchase a secondary sender domain to send more emails
• Their company is completely new to email marketing
• They've planned to use a sender domain that was used sparsely
When you send a huge number of emails from a new or sparsely used sender domain, mailbox providers will be suspicious about your emails and might flag them as spam and deny inbox placement. To prevent this, you must warm up your sender domain.
What is domain warmup?
Domain warmup is the process of building a positive reputation with inbox providers, which will help in achieving inbox placement and in avoiding email throttling and email quarantining.
In practice, warmup means starting with a small number of emails sent to your most engaged contacts and increasing the volume gradually while you watch your bounces, spam complaints, and engagement. Before your first send, make sure you've completed domain authentication for the sender domain. For a step-by-step guide, see how to warm up your sender domain.
What if I don't warm up my sender domain?
Mailbox providers are tirelessly working to provide a safe email experience for their users. When you send emails from a new sender domain that is not warmed up, your marketing efforts might be in vain due to the following:
Your emails will be rejected
Mailbox providers have strict spam guidelines and will often reject emails that are sent from a sender domain that has negative reputation or no reputation. When you send emails from a sender domain that is not warmed up, your emails may get rejected. Authentication matters here too: Gmail and Yahoo require senders of 5,000 or more emails a day to authenticate with SPF, DKIM, and DMARC, and Outlook.com, Hotmail.com, and Live.com apply the same rule, so email that doesn't meet it can be rejected or sent to the junk folder.
Your emails will be quarantined
Since spammers mostly use new sender domains to blast emails, when mailbox providers receive emails from sender domain that has no reputation, or when they receive emails that resemble spam, they will queue those emails in their server and scan them for potential threats. If you send emails without warming up the sender domain, your emails will be flagged as suspicious and will be stored in mailbox provider's server and scanned for threats.
Your emails will be classified as spam
Mailbox providers offer inbox placement based on sender domain's reputation. If you send thousands of emails from a new sender domain which has no reputation, your emails will be marked as spam.
Email engagement and ROI will be affected
When emails don't land in the inbox or when emails are flagged as suspicious, your recipients will be less likely to open them or click on anything inside, thus email engagement will be seriously affected. Lack of engagement will obviously lead to a decrease in your ROI.
Your domain will be blocklisted
When a considerable number of your emails are marked spam, your sender domain will earn a negative reputation. If the sender domain keeps earning a negative reputation, there are chances for it to get blocklisted. Google asks senders to keep the spam rate reported in Google Postmaster Tools below 0.10% and never reach 0.30%, and Yahoo recommends staying below 0.3% as well.
Takeaway
Mailbox providers like Gmail, Outlook, Yahoo, and Zoho Mail consider domain reputation to offer inbox placement. If you are planning to use a new sender domain, you must build a healthy reputation by sending small volumes of wanted emails to your most engaged contacts first, such as people who have recently opened or clicked, and then increasing the volume gradually. A sudden jump to a large volume is what makes mailbox providers suspicious.
Also, when you are planning to send high volume of emails, it is advisable to split the total number of emails and send them either at a regular interval or on a daily basis and stretch the time duration as much as possible to avoid email throttling. Treat any sudden, large increase in your regular volume the same way.
If a considerable number of your contacts use Gmail, you can use Google Postmaster Tools to monitor how Gmail treats your sender domain. Google has retired the Domain and IP Reputation dashboards, so watch the Spam rate and Compliance status dashboards instead. For other mailbox providers, you can run a test email campaign with your test accounts and use the inbox placement result to identify the reputation your sender domain has earned.
Though domain warmup may sound complicated, it is an effective practice with which you can improve email deliverability and email engagement.
If you have any questions, feel free to reach out to us at support@zohocampaigns.com. Our deliverability experts will be more than happy to answer them.