Best Tactics To Warm-up SMTP and Validate Sending IP

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How to warm up SMTP cold emails B2B

Best Tactics to Warm-up an Email IP


Cold Email Deliverability COMPLETE Guide
The first thing you should have in mind before running cold-email campaigns is to avoid spam folders and inbox your emails. Whether your run B2B email campaigns or B2C cold outreach, you should be aware of how email spam filters work and how to validate your sending servers to make your campaigns delivered. 
Internet Service Providers (ISPs) work to detect bot-made emails and remove them from priority inboxes or send them directly to spam folders. When mass mailing is sent to a high volume of recipients and is coming from a new IP address, it may raise a red flag. This means that if you want your emails to go straight to your customers’ inboxes without fail, you must first establish a good reputation in the eyes of the ISPs. In simple words make your emails human.
This reputation is called email-validation.

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What is IP warm-up?

IP (or SMTP) warm-up refers to the process of establishing a good sender reputation that will allow you to send more emails directly to subscribers’ inboxes. 
It is worth noting that you only need to warm up your IP if you use a dedicated IP address to send emails to your subscribers. You do not need a warm-up if you use email marketing services offered by marketing automation platforms like ConvertKit or Sendinblue as these platforms send emails using their own IP addresses.  HOWEVER, while using their IP is the default option, if they will monitor that your campaign’s opening rates are utterly low, or if your bounce rate is high, the email marketing platform will probably ask you to stop using their IP, which may also lead to the inactivation of your account and loss of your data. Having that in mind, you want to keep your email marketing performances excellent, never mind the type of IP you are using.
You should also be familiar with the various types of warm-ups.
Warm-ups are classified into two types: manual and dedicated. If your dedicated IP address is brand new, you may need to warm it up manually. On the other hand, if you add a new IP address to an already warmed-up IP address, an automatic warm-up should suffice.

Factors that determine the reputation of your IP address

IP addresses are evaluated by ISPs based on three key criteria:

1. Bounce Rates

Bounced emails are those that your intended recipients did not receive, and they returned or “bounced” back to you. 
Your emails can bounce for various reasons, the most common of which is that your recipient’s email has been inactive for a long time or that your recipient no longer has access to that account. Your emails can also bounce if the server is under construction. 
Companies will often purchase or rent an existing email list without verifying whether the addresses are valid. These lists can include a high volume of invalid email addresses, and sending out emails to these addresses consistently can result in higher bounce rates. To maintain a good sender reputation, you must strive for 0% bounce rates.
The perfect tool for a fruitful warm-up
Are you having problems with email deliverability? Turn to Warmup Inbox. By helping you build a positive sending reputation, this tool will address all of your deliverability issues and ensure that your emails reach the inboxes of your intended recipients. Warm-up Inbox automates the process of warming up and preparing your IP address for email outreach. Visit Warmup Inbox website today if you want to streamline your warm-up routine.

2. User Interaction

Your recipients’ responses to the emails you send can also have a huge effect on your sender reputation. 
When people receive emails from unknown addresses or promotional emails, they often mark them as spam because the content is not relevant and/or important to them. This act can have a detrimental effect on your reputation as a sender. 
If you are repeatedly identified as a spammer, ISPs will assign you a low reputation score. This means that your emails will never reach your intended recipients’ inboxes. Therefore, it is crucial to deliver only value-rich and relevant content to your recipients.

3. Your Email Content

It would help if you also exercised caution when crafting your emails, as even the smallest of errors can have some severe consequences. If your email includes blacklisted domains, spammy keywords, or links, it may be labeled spam. As a result, your sender’s reputation will suffer.

How to warm up your IP?

As previously mentioned, you will need to boost your IP address’s reputation to avoid being reported as a spammer, which can be achieved by IP warm-up. 
It is a good idea if you “take it slow.” 
To put it another way, start with low-volume email campaigns to earn the trust of ISPs, then gradually increase the number of emails you send until you hit your target number. When you start with a smaller number and send to valid email addresses consistently, ISPs start recognizing you and become more lax with your emails. This helps you pave the way for a solid sender reputation. 
For example—if your goal is to send 100 emails each day, you should begin by sending 20 emails on day one, 40 on day two, 60 on day three, and so on.

A good warm-up requires at least four weeks of continuous mailing with a gradual increase in the daily target. Furthermore, the email addresses to which these emails are sent must be valid and active to avoid bounces. 

You need to identify your most engaged subscribers and send out emails to them during your warm-up sessions. Make sure to grow your email list organically to steer clear of any invalid email addresses.

Do’s for a healthy IP warm-up

  • Only send out value-rich or transactional emails to your target audience.
  • Make sure you are sending emails to active users to maintain a 0% bounce rate. 
  • Add an “Unsubscribe” button under all of your emails. 
  • Always include your business logo and contact information in your email signature.
  • Build an existing customer list ahead of time so you can send emails to everyone on the list when you are getting your IP warmed up. Your existing customers will welcome your emails because they will already be familiar with your brand.
  • Stay on top of your sender reputation score, warm-up schedule, user interaction, and bounce rates. 

Don’ts for a healthy IP warm-up

  • Sending promotional emails when warming up is never a good idea because they are usually reported as spam, which will only weaken your sender’s reputation.
  • Do not continue to send emails until you receive a perfect sending score.
  • Do not rotate IP addresses—IP rotation applies to the method of swapping proxy IP addresses.