A reverse DNS PTR record links an IP address back to a domain name, the opposite of a normal DNS lookup. For mail servers this is essential: receiving servers often check whether the sender’s IP address has a valid PTR record matching the hostname. Without it, your email is more likely to end up in the spam folder or be rejected outright. In this article you’ll learn what a PTR record is, why it’s needed, and how to set it up.
What is a reverse DNS PTR record
Normal DNS translates a domain name into an IP address (A record). A PTR record does the opposite: it translates an IP address back into a domain name. This is stored in a special zone belonging to the IP block, not to your own domain. That’s why you usually can’t change a PTR record yourself through your domain management, but must do so with the party that manages the IP address, often your hosting provider or VPS provider.
An example: the IP address 203.0.113.10 belongs to mail.example.com. With a valid PTR record, a receiving server looks up this IP, finds mail.example.com, and then checks whether that hostname points back to the same IP (forward-confirmed reverse DNS). If it matches, that’s a strong signal of trustworthiness.
Why is a PTR record important for email
Spam filters use reverse DNS as one of many signals to determine whether a message is trustworthy. A mail server without a PTR record, or with a PTR record that doesn’t match the hostname in the SMTP banner, is often considered suspicious. Some receiving servers will even reject mail entirely if there’s no valid reverse DNS.
Besides the PTR record, SPF, DKIM, and DMARC are essential for good deliverability. Together they form the foundation for reliable business email. If you’d rather not figure this out yourself, business email with correctly configured DNS records is often the fastest solution.
Setting up a PTR record in practice
Because the PTR record belongs to the IP address, you don’t set it up through your domain registrar but through the manager of the IP block. On a shared hosting environment, this is usually already set correctly by the provider. On a VPS or dedicated server, you often need to request or set it up yourself through the client panel.
Determine the IP address of your mail server
Check which IP address your server uses for outgoing email. If you use multiple IP addresses, each one needs its own PTR record.
Request the PTR record from your provider
Go to the control panel of your hosting or VPS provider and look for the reverse DNS or PTR record option. Enter the desired hostname, for example mail.yourdomain.com.
Make sure there’s a matching A record
Through your DNS management, for example with your domain names, create an A record that links the hostname back to the same IP address. This is needed for forward-confirmed reverse DNS.
Set the same hostname on the mail server
Check in Plesk or your mail server configuration that the HELO/EHLO name matches the hostname in the PTR record.
Wait for propagation and test
DNS changes can take some time to become visible everywhere. Afterwards, check that everything is set up correctly.
Checking a PTR record and solving issues
You can check the PTR record of an IP address using online reverse DNS lookup tools or via the command line with an nslookup or dig command on the IP address. Check whether the result matches the hostname you expect.
If you can’t resolve it, for example because your provider doesn’t offer the option to change the PTR record yourself, that’s a good moment to consider a provider where reverse DNS, SSL, and email security are properly arranged by default. If you’re wondering whether switching to Tandata makes sense, you can have this handled during the migration so your mail server settings are set up correctly right away.
Frequently Asked Questions
Can I set up my own PTR record?
No, a PTR record belongs to the IP address and is managed by the owner of that IP block, usually your hosting or VPS provider.
What happens if I don’t have a PTR record?
Many mail servers consider email without a valid PTR record suspicious, causing messages to end up in the spam folder or be rejected.
Does every IP address need its own PTR record?
Yes, if you use multiple IP addresses for outgoing email, each one needs its own PTR record matching the correct hostname.
Is a PTR record the same as SPF or DKIM?
No, PTR, SPF, and DKIM are different checks. They work together to assess the trustworthiness of a mail server, but don’t replace each other.
Where can I find my mail settings to check the hostname?
This is usually found in your server management, for example in Plesk under the mail server settings, or you can ask your provider.
Conclusion
A reverse DNS PTR record links your IP address back to a hostname and is essential for reliable email delivery. You don’t set it up through your domain but through your hosting or VPS provider, with a matching A record and a corresponding hostname on your mail server. Correct configuration prevents your email from being flagged as spam.