Email Marketing

The building blocks of inboxing

With the sheer volume of emails being sent every day, email service providers are becoming more stringent in filtering out spam. That’s why optimizing email deliverability is key to reaching your audience. In fact, the average daily volume of emails sent and received is expected to reach 347.3 billion in 2023, marking a 4.3% growth compared to 2022. Projections indicate that this upward trend will continue in 2024, with an estimated increase to 361.6 billion emails, maintaining a similar growth rate.1

Email marketing itself continues to have an ROI that is hard to beat: $36 for every $1 spent.2 This can be even higher depending on the industry. Marketers, you know what this means: it’s time to focus on deliverability and inboxing. After all, if your messages aren’t reaching your audience, you might as well light your budget on fire. Studies show that 37% of brands are increasing their email marketing budget allocation.3 Make that increase mean something.

At the end of the day, it’s simple: the more you send, the smarter you need to be about how you send your mailings. A good way to do that is to implement best practices for “optimal inboxing.” Let’s start with the basics.


What’s inboxing? Delivered vs Deliverability

Inboxing is all about whether your email successfully lands in your subscriber’s inbox or gets lost in the digital wilderness. A common misconception is that an email delivered implies that it made it to the recipient’s inbox. False. Delivered is only confirmation that the email was received by the ISP (Gmail, Yahoo, Microsoft) and was not rejected (soft or hard bounce). Deliverability refers to the ability of an email to reach the recipient’s inbox or desired folder. So, while your email may be accepted by the ISP, it might still be placed in the spam folder. This is why you want to maintain a high inboxing rate – meaning a high deliverability rate. Although the ideal inboxing rate is 100%, strong deliverability (depending on industry) is considered anywhere from 85-95%.


Why does inboxing matter?

To achieve those high conversation rates, your emails must first get into the subscriber’s inbox. You can have the most amazing email content in the world, but if it’s not reaching your subscribers, it’s not going to have any impact. It’s like throwing a party but no one shows up. Sad, right?

The higher your inboxing rate, the more subscribers will see your email, which means better chances for opens, clicks, and conversions. Conversely, a low inboxing rate means fewer people will interact with your email, leading to lower engagement and conversion rates.

While deliverability might not be at the top of your priority list, it’s arguably the first and most important step to ensuring your mailing program succeeds. It is a constantly evolving process, and changes in email technology and best practices can impact deliverability.


What determines your inboxing rate?

Different ISPs have different algorithms to determine how well (or poorly) your emails will inbox. While there are a variety of factors that determine your inboxing rate, these are the ones that you can control:

  • Content and formatting
  • Clean data/mailing lists
  • Mailing strategies, volume and frequency
  • Authentication and configuration


Other factors that impact inboxing, whereby monitoring and adjusting your strategies will play a larger role, include subscriber engagement, sender reputation, bounces and spam traps, and blocklistings. Check out our handy Best Practices card below for an easy breakdown.

Want to monitor and optimize your deliverability? We can help!

If you’re tired of wondering why your emails aren’t reaching their destination and your campaigns aren’t achieving the desired results, we’re here to help! At Inboxable, we offer a range of metrics and indicators that track important factors such as inboxing rates, IP/domain reputation, blocklistings, and spam complaints. Our team of deliverability experts will not only monitor your campaigns but also provide recommendations and proactively troubleshoot any issues we identify on your behalf.

Don’t settle for mediocre results in your email marketing endeavors. With our expert guidance, you can take your email marketing strategy to the next level and achieve the results you’ve been looking for!

Get in touch


Editor’s Note: This Q&A with our Inboxable experts was originally published in May 2017 and has been updated for accuracy and comprehensiveness in July 2023.


Meet the expert
Stephen Taunt
Stephen Taunt
Senior Deliverability Analyst

Stephen Taunt is a Senior Deliverability Analyst on the Inboxable team at Data Axle. With over a decade of data and client relations experience under his belt, he has worked within multiple industries ranging from the music business to global aviation media. Stephen’s passion for all things deliverability help drive his clients' success, leveraging data-driven and strategic tactics.

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