Tips for improving your Gmail deliverability

As Gmail turns 10 this month, I wanted to share some of my experience with deliverability recently. In our expansions to new markets we have been finding some clients coming on board with a majority of their database consisting of Gmail recipients. And with the continuous development of the Gmail filtering system it is becoming more and more difficult to get your email to the Inbox. They have new features such as Inbox tabs/category labels and priority inbox.

We are running into scenarios where emails are going straight to the SPAM folder even though email best practices were applied. Like other ISPs, Google’s email platform is for the recipients, not senders and they are therefore challenging marketers to actually build relevant content, use valid address collection methods, and constantly manage their lists. Gmail launched in 2004 and in 2012 it claimed to have over 425 million users globally. I would imagine this number has increased over the past couple of years. (http://googleblog.blogspot.co.uk/2012/06/chrome-apps-google-io-your-web.html). The days of batching and blasting emails is long over, and getting to the Inbox in Gmail is a constant reminder of this.

Now more than ever Marketers need build campaigns based on behavioral data and consent. Here is a list of items that will help you improve your Gmail deliverability. But before I list the items it is important to remember that the filtering logic is self-learning and constantly evolving. These suggestions will help improve the deliverability but at the end of the day we do not know the exact reason Gmail placed your email to the SPAM folder, outside of the canned ‘Why is this message in SPAM’ heading above filtered messages.

1. Use a dedicated IP address
   • This will allow you to maintain your own sender reputation.
   • It is important to maintain a strong reputation, which can be measured at senderscore.org so that your email at least gets to Gmail.
   • This is a clear indication of to all email providers of your trustworthiness.
2. Authenticate messages with DKIM, SPF, and DMARC
   • Gmail requires a minimum 1024 bit DKIM key and this is available through our Deliverability Cloud Service packages.
   • They do not authenticate messages with keys lower than 1024 bits.
   • DKIM signs the FROM address domain to allow authentication of the sender domain.
   • SPF records identify which servers are authorized to send mail on behalf of your domain.
   • Emails that don’t have SPF or DKIM go through a higher filtering process than those messages that have authentication in place, and in the case of SPF may result in rejection of the message. 
   • DMARC allows senders to indicate to receivers how they authenticate with SPF/DKIM and what to do with messages that fail those checks

3. IP Warming is a MUST
   • Gmail does not like new IPs with no reputation. This goes back to the SenderScore in point 1.
   • I would recommend a minimum 4 week IP warming plan be conducted to get good reputation on the IP and within Gmail.
   • The campaign must be based on recent behavioural data. I would even build it out as a separate campaign for Gmail so you can monitor its delivery and address any issues in the process.
   • Start slow. Only a few hundred messages per IP over the first few days.
4. Get CONSENT and Manage Activity
   • ONLY send email to addresses that have explicitly opted in. Single opt-in will suffice but Confirmed opt-in is recommended. Sending email to Gmail recipients on an opt-out basis will almost guarantee junk filtering.
   • Remove inactive addresses from your lists over time. If certain recipients never open or click through your emails, they are hurting your reputation at Gmail. Remove them, send them a ‘manage subscriptions’ campaign or significantly reduce the amount of mail you send them.
5. Be CONSISTENT
   • They really like if the messages is coming from the same IP and bounceback address. This allows them to more accurately assign reputation to the address/IP pair.
   • Use one specific bounceback address for Gmail recipients. If on the same IP, you can use different Bounceback addresses for each email stream (transactional vs promotional for example).
   • Where possible, segment different email streams by IP.
6. ‘Mark as SPAM’ button
   • One of the key indicators to Gmail that the recipient doesn’t like your emails. We recommend keeping this complaint rate down below 0.01%. While you won’t get complaint data from Gmail to know which addresses have flagged you as spam, you can use data from other ISPs (via the SPAM Unsubscribe report in Eloqua) to gauge your potential complaint rate at Gmail.
   • This is where you need to build content based on previous behavioural data and explicit customer information.
7. Ask recipients to add you to their Gmail address book.
   • This is an enormous step to ensure the email always gets delivered to the inbox.
   • Try creating a dedicated email header for Gmail segments that informs the recipient how to add them to the address book and how it will help deliver your important messages.
8. ‘Not SPAM’ button
   • This is the second most important factor to help messages to arrive into their inbox
   • If users click the ‘Not SPAM’ button after a messages was delivered to their SPAM folder, it is a clear indicator to Gmail that this email is relevant to the recipient and helps their filters adjust categorization of future messages.
9. Avoid using email URL shorteners
10. Avoid pushy subject lines or anything that ‘looks’ spammy.
    • For transactional mail, indicate this in the subject line (eg: ‘Invoice’, ‘Order Confirmation’, etc).
11. MONITOR your affiliates
    • What affiliates do on your behalf can hurt your brand reputation. Ensure they adhere to the same standards as your own marketing team.

I hope you find these guidelines useful and launch successful campaigns to Gmail. Please share your thoughts and experiences with the community so that we can all learn and become even better marketers.

Special thank you to Sweeney Williams for helping out with this post!