How to Use PTR Records to Improve Email Warmup and Deliverability

A PTR record is a type of DNS (Domain Name System) record that maps an IP address to a domain name. Without this, your emails may probably end up in spam or junk. It is considered as an anti-spam police and has significant contribution with the verification and legitimacy of an email server — alongside other email authentication processes, such as SPF, DMARC and DKIM. This process is known as reverse DNS lookup.

Email providers and spam filters use PTR records or ,reverse DNS lookup, to verify that the IP address sending emails corresponds to its assigned and expected domain. 

Some email providers (especially corporate mail servers and certain ISPs) may reject emails from IPs if a PTR record is missing, misconfigured, or considered illegitimate. You can also  receive some errors and every email’s IP address may be considered as spam. 

PTR Records and its Contributions for Email Deliverability

• Spam Prevention: Many mail servers and spam filters check for a valid PTR record before accepting emails.
• Reputation Building: ISPs and mailbox providers trust senders with properly configured DNS PTR records more than those without.
• Bounce Rate Reduction: Emails sent from an IP without a PTR record may be rejected outright.
• Essential for Email Warmup: During the warmup process, email service providers verify sender reputation, and a missing or incorrect PTR record can harm credibility.

PTR Records In Improving Email Warmup

Email warmup is the process of gradually increasing your email-sending volume to establish a positive reputation with ISPs. Without a valid PTR record, many of your warmup emails may be flagged as spam or rejected by receiving mail servers.

How PTR Records Support a Smooth Email Warmup:

Improved Email Authentication 

Having a proper PTR record DNS entry minimizes the possibilities of your emails being marked as suspicious. Hence, you need to verify if your IP address has properly configured PTR record and employ other authentication procedures.

Enhanced ISP Trust 

A completely configured PTR record represents a legitimate sending infrastructure. Various  mailbox providers that use PTR records as part of their email filtering criteria. 

Higher Inbox Placement

A correctly configured PTR record is a good first step, but not sufficient. Using other authentication systems such as SPF, DKIM and DMARC to improve your inbox placement rate.

Lower Spam Complaints

PTR record contributes in establishing a good sender reputation, thus minimizing your spam complaints. 

Configuring a PTR Record

It is important to understand that PTR records are tied up to an IP address. To properly set up a PTR record you need to work alongside your Internet Service Provider (ISP), or your hosting provider. 

Step 1: Check if You Already Have a PTR Record

Before setting up a new PTR record, perform a PTR record lookup to determine if an existing one is in place.

How to Perform a PTR Record Lookup:

1. Open a command prompt (Windows) or terminal (Mac/Linux).

Enter the following command:
nslookup <your IP address>

1. Example:
   nslookup 192.168.1.1
2. If a PTR record exists, the output will display the associated domain name.
3. If no PTR record is found, proceed with configuration.

Step 2: Get in Touch with Your ISP or Hosting Provider

PTR records must be set up by the ISP. Your ISPs control your IP range, hence they have the ability to update your PTR record. 

• Reach out to your ISP or hosting provider and request a PTR record update.
• Provide your public IP address and the domain name you want it mapped to.
• The provider will configure the PTR record DNS settings on their end.

Step 3: Verify the PTR Record Setup

After your ISP has added the PTR record, perform another PTR record lookup using the method mentioned in Step 1 to confirm that the changes have taken effect.

Step 4: Monitor Email Performance

Once the PTR record is correctly configured, monitor your email deliverability metrics:

• Check for bounce rates and spam complaints.
• Ensure emails reach the inbox instead of spam folders.
• Gradually increase sending volume as part of the email warmup process.

PTR Record Example

Here’s an example of a properly configured PTR record:

• IP Address: 192.168.1.1
• Domain Name: mail.yourbusiness.com

PTR Record Entry:
1.1.168.192.in-addr.arpa. IN PTR mail.yourbusiness.com.

This setup ensures that any mail server performing a PTR record lookup on 192.168.1.1 will see it mapped to mail.yourbusiness.com, verifying its authenticity.

Common Issues with PTR Records and How to Fix Them

No PTR Record Found

• Issue: Some ISPs do not configure PTR records by default.
• Solution: Contact your ISP and request the creation of a PTR record for your sending IP.

PTR Record Mismatch

• Issue: The IP address maps to a different domain than expected.
• Solution: Ensure that the domain used in the PTR record DNS entry matches your sending email domain.

Slow DNS Propagation

• Issue: Changes to PTR records may take up to 24 hours to fully propagate.
• Solution: Allow time for DNS updates to take effect before retesting.

Additional Best Practices for Email Deliverability

PTR records are just one of the many requirements for acquiring a reputable and trustworthy email domain. On its own, PTR records may not have the proper maintenance to establish a health email domain.

Incorporating email warm up services such as Warmy.io can supply the necessary system to contribute with the improvement of your email deliverability. 

Warmy.io is known for its free email deliverability test. This helps you evaluate any problems you can encounter that might damage your deliverability. 

It also has free SPF and DMARC records generators — essential email protocols that are needed other than a properly configured PTR record. 

Warmy.io is also an ideal tool for your overall email system needs. It provides features such as:

Email Warmups

A new or inactive email address does not have any established reputation yet. If these types of emails suddenly send a high volume of emails, ISPs can consider these as spammy. 

Warmy’s email warm-up process prevents your emails from being marked as spam by gradually and automatically increasing the sending volume. 

Our email warmups can send up to 5,000 emails per day in a way that avoids suspicion and helps build a reputable email domain.

Warmy automates this process, making it easier to establish credibility with email service providers.

Domain Health Hub

Warmy’s Domain Health Hub has been upgraded to a more advanced and professional level, it can now assess every statistical data at a domain level. Users will gain complete monitoring of their deliverability at the domain level instead of their individual inboxes. 

• Instant Domain Health Score: Check your deliverability status with metrics such as Inbox Placement, DNS Authentication, and Google Postmaster Data.
• Clear Warm-Up Performance Insights: Gives you the ability to track spam rates, inbox placement, and deliverability trends weekly and monthly.
• Comprehensive DNS Status Checks: Validate and troubleshoot SPF, DKIM, DMARC, rDNS, MX, and A records for seamless email authentication and security. 
• Optimized Multi-Domain Monitoring: Manage all your domains from one sleek dashboard. Making it easier to identify which ones need immediate action. 
• One-Click Deep Insights: Click on any domain to access detailed health metrics, performance reports, including deliverability trends with ease. 

Email Seed List

Seed listing is one of Warmy’s advanced deliverability systems.

It has the flexibility to be integrated into any email client, and improve your email performance testing. Warmy will supply genuine email addresses from Gmail, Outlook — and very soon, Yahoo— that will act as seeds for testing your email deliverability. 

It will simulate real engagement to improve sender trust, and if in case that your emails are sent to spam, it will be removed from spam and marked as important to program ISP into understanding that your emails are legitimate. 

Customer Success – Support & Deliverability Consultant

Who knows your way around our services but maybe you need help with things like deliverability or how to get the most out of our services? We offer 24/7 Zoom calls and other chat support to help you navigate through our system! We want to help you reach your long-term goals, while making sure your emails are delivered and your reputation is intact.

DNS Records Testing 

Warmy.io have a DNS records testing which can help you test up to 100 DNS records maintaining an optimal email deliverability, and plays an essential role in determining whether your emails will reach your recipients’ inboxes or get caught in spam filters

Sign up for the 7-day free trial, or book a demo and witness your email engagement soar!