Sending an email to a recipient’s inbox is the first step to a successful campaign. The best offer, creative, and subject line won’t matter if the subscriber never receives the message.
In this article, I will explain how to prevent email providers such as Gmail, Yahoo, Outlook and others from blocking delivery or routing to spam or bulk folders.
Email marketing platforms – Mailchimp, Sendinblue, and many others – show the percentage of emails “delivered”. But this includes messages in spam and mass folders. So a 99% deliverability rate might sound good, but it doesn’t mean the recipients saw the email. I don’t know of a tool that calculates the number of emails that have arrived in inboxes.
Email platforms only count hard bounces – those sent to non-existent addresses – as undeliverable. Most platforms automatically delete these addresses.
Soft bounces are usually temporary hangs, such as inboxes full or unavailable or sudden increases in volume at that address. Most email platforms return soft bounces multiple times. But they usually count soft bounces as deliverable, resulting in a misleading rate.
Soft bounces used to only occur when an inbox was “full”. However, this is no longer the case as most providers offer larger inboxes for users and rarely hit storage limits.
Here are three indicators of deliverability issues.
- Decreased opens and clicks. A breakdown of subscriber domains – i.e. @gmail.com, @yahoo.com – can reduce the problem. For example, open rates for Yahoo addresses suddenly dropping from 12% to 4% could indicate blocking or filtering of spam folders.
- Increase in unsubscribes. An increase in unsubscribes is probably not a deliverability issue. But it can infer user engagement, which impacts inbox reception. An increase in unsubscribes could mean weaknesses in messaging, frequency, or overall sending strategy.
- Sender score degradation. Weekly monitoring of your IP address and domain reputation is essential to maintaining the health of your email program. Sender Score, a free service from Validity, formerly Return Path, is my tool of choice. It assigns a score from 0 to 100, with 100 being the best.
Impacts on deliverability
Senders. A sender’s history and practices affect deliverability. Senders with consistent and responsible email volume and frequency over time typically have high sender scores.
Recipients are the essential factor of deliverability. Email providers view overall subscriber engagement as a key indicator of deliverability. If subscribers continually delete an email without opening or clicking, the provider will likely automatically filter the emails into a spam bucket. This could lead to a total blockage. Thus, senders must periodically delete unresponsive subscribers.
Email providers seek to reduce spam and unwanted messages for users while delivering legitimate senders to the inbox. It can be tricky. Providers change algorithms frequently to stay ahead of spammers. Unfortunately, the changes often trap legitimate senders.
Third-party blacklists such as Spamhaus and MX Toolbox maintain accounts of spam domains and IP addresses. Email providers include these lists in their algorithms. Sometimes responsible senders are mistakenly added to blacklists. So it’s a good idea to make sure your domain or IP is not included. If so, a short email to the blacklist service will usually resolve the issue.
Apple Mail Privacy
Apple’s Email Privacy Protection lets iOS 15 and macOS 12 Monterey users not disclose whether they’ve opened an email. apple watch now everything emails to these users as having been opened. The result is inflated open rates. Email providers adapt their algorithms accordingly.
The impact of MPP on marketers has been mixed. This only affects iOS 15 and macOS 12 users who open emails on the Apple Mail app and have privacy protection turned on. Android has not (yet) rolled out a similar feature.
Early data from Sendgrid, the email delivery platform, suggests less than 5% of Google (Gmail) and Microsoft (Outlook) opens use MPP compared to around 23% of Apple Mail opens.
Either way, marketers will increasingly value click-through rates, not opens, as the primary metric of email engagement. Tactics to encourage clicks, such as short content and compelling calls to action, will become commonplace.
In short, to improve deliverability:
- Avoid large changes in volume or frequency.
- Monitor open, click and unsubscribe rates.
- Check your sender score and major blacklists.
- Keep your list healthy by deleting unresponsive subscribers.
- Implement strategies to improve clicks.