Top tips to keep Emails out of spam folders

With Email being such a vital utility it’s important that your emails get to where they need to be. Keeping emails out of junk folders can be hard. This article provides some top tips on how you can ensure you keep emails out of spam folders.

IP Reputation

Probably the most important thing to consider is your IP reputation. IPs are recyclable and it’s possible the user before you mistreated their IP. If someone has sent spam from your IP previously your reputation will be poor. Similarly, if the IP was used on a VPS Server and then sent lots of mail every day the IP is likely to be rate-limited.

Reputation is earned and not assigned right away. If your IP is new which is very uncommon these days it won’t have any reputation. Running your server well, and ensuring you don’t send spam will increase your reputation over time.

RBL Listings

An RBL is a database of IPs that, for the most part, have been observed sending spam. IPs on RBLs will cause email deliverability issues. We say for the most part because some RBLs like Spamcop tend to list entire IP blocks. You can search your IP on an RBL and apply to have it removed if it’s listed. which should be done as soon as possible.

IP rDNS Records

An rDNS or PTR record is a reverse of your domain name. Mail servers check to see if your IP has a PTR record and if it doesn’t your IP will be seen as a higher risk of sending spam. Your support team can configure rDNS entries for you. Your rDNS entry will usually be your domain name or your server’s hostname. Usually, it’s best to go with your server’s hostname.

Mail Helo

Another way to help keep emails out of spam folders is your server’s mailhelo. A mailhelo is the initial communication between a mail server and a client. If you send mail from your server’s main IP then the mail helo will be your hostname. If you have your server configured to send mail from each account’s dedicated IP you need to configure Exim to reference the mailhelo file. This file is usually located at /etc/mailhelo and is formatted like the below code;

domain.com: domain.com
sub.domain.com.com: domain.com
exampledom.net: domain.com
addon.exampledom.net: domain.com
*: hostname.domain.com.com

abuseat.org has a great way to ensure your mailhelo is correct. Just send an email to [email protected] from your server and read the bounced reply.

SPF Records

An SPF record is a record in your domain name’s DNS Zone file and should match the IP that the site is hosted on. SPF records are always in the format;

"v=spf1 +a +mx +ip4:52.31.73.14 ~all"

Having the wrong IP in your SPF may cause emails to go into spam or junk folders.