3 ways to get from the junk box to the inbox

7 minute read

Spam filters have become incredibly intelligent – they’ve had to evolve as spammers come up with new and exciting ways of getting their malicious messages through. However, sometimes legitimate marketing emails get caught up in the filters and marked as spam. While this definitely isn’t a guide on how to ‘cheat’ a spam filter, here are three things you can do to get out of the junk box and into the inbox.

Spam filter

1. Sort out your from address

You can have the most amazing content in the world, but if the configuration for the domain of your from address isn’t right then all your beautiful emails are far more likely to end up in the junk folder. If you’re using an external bulk email provider (like Sign-Up.to) to send your email marketing, then you should set up an SPF record on the domain of the from address you use. Major ESPs like Hotmail and Gmail use SPF to screen emails and make sure they’re authentic. For example, when sending using Sign-Up.to, including our domain in your SPF record tells the ESP that our mail servers are authorised to send emails on behalf of your domain. It’s not a magic bullet, but correctly configuring SPF can improve inbox placement and reduce bounces.

Your from address reputation is also used by filters to decide whether or not your emails are junk. Check that your from address domain isn’t blacklisted using MXToolBox or try split testing with a different from address domain to see if that helps. While changing the from address domain can help diagnose the issue, it can also negatively affect campaign results – subscribers may not recognise your emails if you change it frequently, and it reduces the positive impact of subscribers whitelisting one specific from address. Don’t rely on frequently changing your from address to avoid the junk box – instead try to improve the reputation of your from address domain (send good content to engaged subscribers). The long term benefits of consistently sending from a single from address domain with a good reputation far outweigh any temporary benefits from switching between throw-away domains.

2. Engagement matters

Engagement has become hugely important in spam filtering algorithms. The large ESPs are increasingly looking at what subscribers do with your emails to decide whether or not they’re spam. If you’re sending to a large but mostly inactive database, the filters will notice that no one ever opens or clicks your emails. Your emails are seen as unwanted, and will end up in the junk folder. Eventually, the ESP might even stop delivering your emails completely.

It’s a good idea to send to your most engaged subscribers first. The ESPs see the initial activity from these recipients, and are more likely to deliver to the inbox of subsequent subscribers. If you use Sign-Up.to, then don’t worry – our email system automatically sends to your most engaged subscribers first.

When designing your email campaign, think about how subscribers engage with it and what you want them to do. Make calls to action clear and concise, and put them near the top of the email so they’re visible in the preview pane. Use responsive email designs, so that subscribers can interact with your emails even when they’re on a mobile device. If you’ve got a lot of educational content, consider a shorter campaign with “read more” links instead of including all the information in the email itself – this encourages clicks through which will further boost engagement. Target smaller audiences of subscribers with really relevant content that they want to interact with. The better your engagement is, the more emails will land in the inbox, giving more subscribers the opportunity to engage, even better delivery, and on and on.

Finally, consider clearing out inactive subscribers from your database. It may seem counter-intuitive, but if they’re not engaged with your campaigns, they’re unlikely to be a source of revenue – and they may even be preventing your emails from reaching the inbox of subscribers who really do want to hear from you. Sign-Up.to clients can use engagement targeting to identify these subscribers. Maybe try sending them a farewell email to give them one last chance to re-engage. If they’re still not interested, it might be time to say goodbye.

3. Check your content

Points-based filtering algorithms are still in use, and if your campaign looks spammy then it’s likely to be filtered. The larger ESPs use them in combination with SPF and engagement, but smaller ESPs and businesses with their own mail servers largely rely on content based filtering. See our old blog post for things to look out for when creating your email campaigns.  

Another thing to take note of is linking to content within your emails. The reputation of the URL domain you’re linking to can affect your delivery (see our recent blog post about delivery issues for people using the link shortener bitly). If you’re linking to 3rd party websites you don’t own, then check them using MXToolbox’s blacklist checker to make sure they won’t negatively impact your email delivery.