Is Email Authentication Necessary to Improve Delivery?
Email authentication was never intended as a way for senders to improve their inbox delivery. Rather, it was meant to protect senders and consumers from fraudsters who try to spoof their well-known domains and brands. The problem with authentication is that adoption rates have been low, therefore internet service providers and mailbox providers aren’t sure if it makes sense to block any unauthenticated email based on the sender’s policy records. While doing so would certainly cut down on fraud, it would also result in blocking a lot of legitimate mail, creating a really poor consumer experience.
To help speed adoption, some ISPs have been dangling a carrot in front of senders. While there are no explicit inbox deliverability benefits of authenticating email, there are plenty of implicit benefits. Yahoo requires senders who want to be signed up for its Feedback Loop (FBL) program to sign all outgoing mail with DomainKeys Identified Mail (DKIM). Yahoo’s FBL program allows you to remove people that report your email as spam, lowering your complaint rate over time, which in most cases can also improve inbox delivery. Windows Live Hotmail also gives a slightly weighted score to your IP address reputation.
Publishing a sender policy framework (SPF) record for your “from” domain may help boost your chances of inbox delivery, but only if the rest of your sender reputation metrics are also solid. Additionally, email providers like Gmail, Yahoo and Windows Live Hotmail place a trustmark next to authenticated email. This helps to build subscriber trust by proving that your email is legitimate.
Based on my own research, nonauthenticated domains see a 1 percent decline in complaint rates for authenticated domains compared to nonauthenticated ones. Authentication and subscriber trust go hand-in-hand, which help improve your sender reputation and deliverability.
Hopefully now you’re convinced that authentication is important. Here are three things you should do immediately: