Email inboxing: Master the art with this checklist

Even if you’re not running an email marketing campaign, email is an essential method to stay in touch with your recipients. So how do you land in your recipient’s inbox? Read on to find out what email inboxing is and some challenges to overcome. We’ll also leave you with five tips to stick that landing.



Remember those good old days of email blasts and cold emailing? Yeah, that doesn’t work anymore. In fact, email deliverability has never been more challenging. Now that you’ve integrated sending into your app or product, it’s time to think about deliverability.

What is email inboxing?

Email inboxing is the rate at which your email makes it to your target audience’s inbox. This takes some art and science and black magic.

As you can imagine, the lower your email campaign’s inboxing rate, the fewer the number of readers who actually see your email and have a chance to engage with it. This means all those marketing metrics take a dip – goodbye open rate, click-through rate (CTR), conversion rate, and engagement rate. Of course, a high inboxing rate means the opposite. Pop open the champagne!

Below, we’ll go through some challenges you’ll face in terms of email inboxing and five best practices to stick that landing in your recipient’s inbox.

What are some email inboxing challenges?

Firstly, landing in your email subscriber’s inbox is harder than ever – even if you’re a reputable sender. Regardless of the types of emails that you’re sending – whether these are email newsletters, product announcements, or mass emails – here are three main challenges when it comes to email inboxing:

  1. Don’t look like spam: We know you’re not a spammy sender, but email service providers (ESPs) and internet service providers (ISPs) nowadays closely monitor signs of spam and potentially malicious activities. Even if you’re a reputable sender, you need to stay on your toes. After all, if you don’t follow proper email etiquette, you may end up on a blocklist, and your messages may never reach your target audience.

  2. Stay relevant: This is easier said than done. However, by creating relevant content, great email designs, and using appropriate email subject lines and calls-to-action (CTAs), you can retain your audience’s attention, ensuring constant contact. If your readers find your messages relevant, they're more likely to open them and click through to your landing page. Some ESPs track low email open rates. If your audience doesn’t open your email messages, ESPs might think you’re sending irrelevant and potentially spammy content. They can refuse to place future emails you send in your recipient’s inbox. Stay relevant to avoid the spam folder.

  3. Optimize your email strategy: Take a look at your metrics. Are you experiencing high bounce rates or low click rates? Adjust your email practices to boost your metrics and your deliverability.

What are the 5 best practices to land in my recipient’s inbox?

So how can you ensure your emails actually reach inboxes? Here are five best practices that you can opt for to improve your email performance:

1. Focus on email list hygiene

Let’s start with something we hammer on about all the time, i.e., keep your mailing list clean. You can do this by:

  • Monitoring bounce notifications. Email bounces and spam complaints are major red flags for ISPs. You can improve your mailing reputation by monitoring bounce notifications. For example, many email services provide feedback loops that tell you when a recipient classifies your message as spam.

  • Removing inactive email addresses. Instead of sending to your entire email list every time, you should remove disengaged recipients who haven’t responded to or interacted with your emails after 90 days. ISPs take interaction, such as opens or clicks, as a positive sign, which improves the sender’s reputation.

  • Having an “unsubscribe” feature. You should have a clear unsubscribe option. While an unsubscribe option is a requirement under the Controlling the Assault of Non-Solicited Pornography And Marketing (CAN-SPAM) Act, it also discourages recipients from filing spam complaints, damaging your reputation.

  • Using double opt-in. This means you’re validating the email entered on your website twice – first by having your recipient enter the address on the website, followed by asking them to confirm their subscription through a confirmation email.

2. Use proper authentication practices

Adhere to authentication protocols. ESPs will assume a sender is spamming and will filter or drop the sender’s email if the emails aren’t properly authenticated. The common types of authentication are SPF, DKIM, and DMARC, which work for both one-to-one and bulk emails.

3. Track your sender reputation

It’s hard to build a reputation, but easy to lose it all in one go. That being said, stay on top of your email sender reputation.

Email reputation is similar to personal credit scores. A poor email track record or no track record at all may prompt an inbox service provider to filter a sender’s message. Conversely, you can use a dedicated IP address to ensure you have full control over your sender reputation.

4. Optimize your email content to improve your email deliverability

This goes without saying, but you can’t compete if your email can’t be delivered. Improve your deliverability with the following tips:

  • Keep your images to a minimum: Too many images and text links send a red flag for inbox service providers, deciding whether or not to place your content in your recipient’s inbox.

  • Send multipart emails using both text and HTML or only text: Sending HTML-only emails isn’t well received by ESPs. Also, ESPs generally block images by default, so HTML-only won’t look great unless readers are proactive about enabling images.

  • Avoid promotional text: Gimmicky promotional text, such as “Buy Now!” or “Free!” are major spam flags. Also, avoid using all caps and exclamation marks.

  • Personalize emails: The content should reflect the recipient’s specific interests or usage patterns and address your recipient by name.

  • Always identify who’s sending the email: Make it easy for your recipient to see who’s the sender. Build trust and a relationship with your readers.

  • Have a clear way to unsubscribe: It’s sad to see your recipients go but ensure they have a clear way to opt out of your emails. Otherwise, they might mark your emails as spam. Too many spam or abuse complaints can land you on a blocklist.

5. Be mindful of your sending volume

You must be aware of the volume of emails you’re sending. For instance, keep in mind that ESPs have send limits for each IP address. High-volume senders (more than 50,000 emails per week) should consider using a pool of IPs.

Conversely, you might want to use a shared IP address if you have a lower sending volume. Organizations that send less than 5,000 emails per week should consider a shared IP, which can help boost perceived sending volume. Many ESPs won’t acknowledge a sender’s reputation if their volume is too low.

However, if you have an established sender reputation and don’t want to rely on how other brands behave on your shared IP, you might want to look into a dedicated IP address.

Lastly, you might want to use a separate IP address for your transactional emails. Time-sensitive transactional emails may get queued behind a large batch of bulk marketing emails. In addition, bulk marketing emails can negatively impact the reputation of transactional emails.

Wrapping up

Senders that keep a close eye on their email performance can take corrective actions before they waste valuable time and resources on unsuccessful email deliveries. By taking a more active role in their delivery efforts, senders can boost their reputation scores and avoid email death traps, such as spam filters or blocklists.

Ready to get cracking? Take advantage of email automation with Mailgun’s Email API, so you don’t have to craft every single email individually. Also, before you send out your next email, see how our Inbox Placement feature can help you see how your email will perform before you hit send.

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