Wondering why some of your emails end up in spam or junk folder while others make it right into the inbox ?

Well, the reason behind it is the reputation of your IP address that is responsible for sending emails.

If your IP address doesn’t have a good reputation for an Internet Service Providers (ISPs), then there comes the possibility that your emails will send to the junk folder.

So, do you need to warm up your IP address to have better inbox deliverability. ?

Warm up your IP if you need to send a lot of emails and want them to land them right into the inbox also if you want to set up an email marketing platform.


Here is a quick guide including 34 best practices which will help you improve email deliverability and build a good sender reputation – 

1. Authenticate The Emails –

Once the emails are authenticated, the sent “via” text will not be shown, and this will upgrade the reputation of the domain name.

This can be done in the following ways: – 

  • SPF – Authentication can be done easily by adding the IP addresses which can send emails via the domain name in the DNS record.
  • DKIM – A public or private key system can be used to sign emails.
  • DMARC – The proper authentication of the emails by the webmail or ISP is evaluated by the sender.

Note – Check How MailGet Handles It Best For You. !!


2. Using A Public Whois –

All the contact information related to the domain name should never be hidden. A public ‘Whois’ should be used which will contain all the essential contact information.

The information will include –

  • All information about the owner.
  • The technical contact information.
  • Information on the host of the domain.

3. Use Forward & Reverse DNS Lookup –

The ISP’s or webmail often check identity by using the DNS (Domain Name System).

Hence, the control panel of the web host account should be used to appropriately configure these settings –

  • The domain name associated with an IP address should be verified using the reverse DNS lookup.
  • The IP address associated with the domain name should be verified using the forward DNS lookup.

4. Adopting A Dedicated IP Address – 

Having a good IP address reputation is very important. The reputation of the IP depends on largely upon the quality of messages being sent and the interactions taking place through that IP.

Hence, having a dedicated IP address with a good sending reputation is very essential.

  • Once a dedicated IP address is adopted, there is no need to share the IP address reputation with others users.
  • Sending consistent volumes of emails is essential for building up a good IP reputation.

5. Warming Up The IP Address – 

The IP warming process should be conducted. This helps in building a good sender reputation.

  • Initially, when emails are sent through new or ‘cold’ IP addresses, the ISP’s or webmail don’t trust them completely.
  • A good IP warming process will ensure that consistent volumes of good quality emails are sent through an IP address over a period.
  • This will establish the IP address as a legitimate sender.

6. Using Separate Email Ids For Transactional & Marketing Emails – 

Any delivery issues can be minimized to a great extent by separating the different kinds of emails which are being sent.

  • Different email addresses should be used for sending transactional and marketing emails.
  • Email service providers like Gmail and Outlook.com have intelligently designed inboxes in which sorting of emails by category is done automatically.

7. The Domain Name Should Be Linked To An Existing Website – 

The sender information is always verified to avoid any spammers.

Thus, linking the domain name to an existing website is very essential.

  • The Internet Service Providers will never trust an IP address which does not direct the readers to an existing website.
  • If the sender is a spammer, then there will be no website created for the sender domain.

Hence, a domain name should always be linked to an existing website to gain the trust of the ISP’s.


8. Making Use Of Email Throttling – 

By using ‘email throttling,’ the speed at which emails/campaigns are sent can be adjusted. Various parameters should be configured to enhance the rate of email deliverability.

They are –

  • The number of emails which are sent every minute or hour.
  • The number of connections every minute or hour.
  • The number of emails which are sent via each connection.

9. Configuring Abuse@ & Post-Master@ Email Addresses – 

Configuring abuse@ and post- master @ email addresses prove very helpful.

  • The abuse@ email addresses receives consumer complaints.
  • The post master@ email addresses receives all the essential information regarding any impending problems of technical nature.
  • Hence, these email addresses should always be configured for the domain name.

10. Considering Return Path Certification – 

The Return Path Certification proves helpful for large email senders.

  • The IP address is certified, and it hastens the delivery of the emails to the inboxes.
  • This certification enables the ‘default display’ of images.

Hence, there is no need for the recipients to click on the message showing ‘display messages’.


11. Using ‘Seedlists.’ – 

Checking each and every contact to find out whether the emails have reached the destination can become a cumbersome task.

It is here that using ‘seedlists’ prove helpful.

  • A group of witness email addresses can be created using this technique.
  • One can easily check whether an email has been properly delivered to the recipient.

12. Monitoring Blacklists – 

The IP address and domain name should always be present in a blacklist.

  • These blacklists which are referred to as RBL OR DNSBL filter incoming emails.
  • Autonomous anti-spam services govern these lists.

Entire networks or some IP addresses are blocked by them.

  • There are various services like Mxtoolbox.com and Blacklistalert.org, which can be used to confirm whether the IP address or domain name is present in the blacklist.

13. Monitoring Spam Complaints & Using Feedback Loops –

The ‘feedback loop’ is an alert which is permitted by a few ISP’s and webmails.

This alert is shown whenever an email is marked as spam.

  • The ISP’s should be informed that notifications should be provided by them in case any spam messages are reported.
  • These complaints should be recorded, and any associated contacts should be removed from the list.

14. Offering A Clear & Instant Link For Unsubscribing – 

Offering a link for unsubscribing is very essential. This minimizes the chances of being classified as spam.

  • The link which is provided for unsubscribing should function smoothly and quickly.
  • Locating the link in the email should also be easy.
  • The users should never be asked to reaffirm their wish to unsubscribe.
  • No assurance should be provided that they’ll not be contacted again.

The users will themselves mark the mail as spam and block the mail address of the sender.


15. Managing Errors – 

The error rate should always be kept to a minimum. The ISP’s associate high error rates to poor sending practices.

  • Whenever certain emails result in errors, they should be immediately looked into.
  • The concerned email address should immediately be deleted from the list.
  • The database remains clean in this manner. There will also not be any inactive or nonexistent contacts.

16. Not Buying Or Exchanging Contact Lists – 

There should be full control over the contact lists, and the recipients of the emails must first agree on being contacted.

  • The lists of email addresses which are commonly found on the internet are copied sometimes.

Hence, they are of inferior quality and should be avoided at all costs.

  • Email databases should never be taken on rent or bought.
  • Tips from friends, colleagues or partners should also not be taken.

17. Using A Double Opt In Procedure – 

The email address should always be validated to find out whether it exists and is properly working.

The double opt in the procedure can be used to do this.

  • This procedure enhances the quality of addresses collected.
  • Authenticating whether the contact is indeed the owner of the address can also be done easily.
  • A confirmation link can be added to the welcome mail, and the validation can be done by simply clicking on the link.

18. Sending Campaigns Regularly –

Emails should always be sent regularly to the contacts. This will also be beneficial for the brand.

  • The lifespan of the memories of contacts is very short.

Hence sending mails to the contacts at regular intervals is very essential.

  • The contacts will also remember what they had subscribed for.

19. Unsubscribing Inactive Addresses – 

It is always better to unsubscribe email addresses which are not active.

  • Often recipients do not respond to mails for longs periods of time.

This either means that the email address is no longer in use or the recipient does not want to communicate any further.

  • This can prove harmful for the sender’s reputation.
  • Therefore it is best to delete such addresses.

20. Creating Multipart Emails – 

The emails should always be composed in the HTML and text format.

  • Creating a text version of emails is essential.
  • The HTML version is not yet displayed on mobile devices by a few clients.
  • The anti-spam filters compare both the text and HTML versions to ensure similarity.

21. Avoiding Image-Only Emails –

The text of the mail should never be replaced by images.

  • The spam mails usually have text hidden in images.
  • This is done so that spam filters can be avoided.
  • So, the spam filters usually avoid such images.

22. Avoiding Words Suggesting Spam/Phishing – 

Words which are frequently used by spammers should be deleted.

  • Use of certain words suggests spam or phishing.

Therefore, such words should surely be avoided.

  • Use of words like ‘free’, ‘credit’, ‘pharmacy’, ‘urgent’ ‘click here’ etc. Should be avoided.

23. Sender Should Be Identifiable – 

The sender of the email should be easily identified by the subscriber.

  • Using the brand or site name as the sender’s address is a good option.
  • The subscriber will be able to easily identify the emails in this manner, and they’ll not be marked as spam.

24. Respecting Good HTML Practices – 

Coding the HTML emails is very essential. The spam filters pay much attention to the quality of coding.

  • Coding HTML can become time-consuming. However, the rules should be followed properly.
  • The tags should be closed, the HTML tags should be written in lower case, and alternative attributes should also be added to images.

25. Visualizing The Email Rendering – 

The designs of emails should be perfect. The reports on various display tips of clients should be tested.

  • Popular providers like Apple Mail, Thunderbird, and Outlook, should be tested.
  • The webmail should also begin with testing Gmail, Yahoo! Mail and Outlook.com.

26. Testing Content In Different Anti-Spam Filters – 

The content should be tested in different spam filters because each of them tests the content differently.

  • Each spam filter reacts differently therefore, it’s good to be cautious and test in each of them.
  • SpamAssassin is the most commonly used filter there are much more like Cloudmark, Postini, and Barracuda.

27. Using Pre Headers – 

The initial lines of the message are displayed just below the object by a few interfaces. This space should be fully utilized.

  • Pre-headers like ‘Click here to see’; ‘See the online version’ are of no use and should be avoided.
  • The lines can be read even if the emails are not opened by the recipients.

28. Avoiding IP Addresses, Link Shorteners – 

The links produced by advertising or URL shorteners should certainly be avoided.

  • The IP addresses should not be used as links.
  • Spammers use such techniques to hide landing pages.
  • The identity of the landing page should clearly be shown in the links used in the emails.

29. Avoiding ‘No Reply’ Addresses – 

Emails should always be received by the senders. Conversations should never be cut off with a ‘no reply’ address.

  • All questions, comments or problems regarding any email should be addressed by using the ‘reply’ button.
  • This will also enhance the customer relations.

30. Increasing Reactivity By Segmenting – 

All the contacts will never have the same necessities or expectations.

  • The contacts should be categorized according to their needs, expectations and how the services are used by them.
  • Personalized subscription options can also be offered.

31. Obeying The Law – 

Having proper knowledge regarding the laws on privacy is very essential.

  • The privacy of the users should be protected.
  • All the information of the users should be stored securely and also authorized by the user.
  • The registration process, legal disclaimer, and usage conditions should be validated and checked.

32. Keeping the promises –

Maintaining a proper and healthy relationship with the subscribers is very essential. Hence, all the promises made to the subscribers should be kept.

  • The users should not be contacted unnecessarily.
  • They might mark the sender as spam if this is done.
  • In case certain rules are changed, the users should be informed and given the chance of changing their preferences.

33. Providing a link to the privacy policy – 

The subscribers will begin to trust the sender if a link to the privacy policy is provided.

  • A web page containing the privacy policy should be created.
  • The contact information should be provided.
  • Providing a phone number will be an additional plus point.

34. Sending invitations to subscribers to add the sender to their address books – 

Mails can be sent very easily and conveniently if the subscriber adds the sender to their address books.

  • This will work positively for anti-spam filters.
  • Once the sender is added to the subscriber’s address book, their emails will never land up in the unwanted folders.

Conclusion – 

A lot of attention should be taken to maintain your IP address to get a good email deliverability rate. Well, I hope these tips can be easily followed up to warm up IP address and to improve email deliverability.

We would love to hear if you have taken a different approach to warming an IP. 🙂