What is email deliverability and how do you improve it?

By Indeed Editorial Team

Published 5 September 2022

The Indeed Editorial Team comprises a diverse and talented team of writers, researchers and subject matter experts equipped with Indeed's data and insights to deliver useful tips to help guide your career journey.

Email deliverability refers to the ratio of how many marketing emails make their way to their destination inbox compared to how many emails finish their journey in spam folders and bins. Most contemporary email platforms include technology designed to identify spam emails and divert them into a spam folder automatically. Increasing the deliverability of your marketing emails means more of your emails reach their target audience, boosting the overall effectiveness of email marketing campaigns. In this article, we explore what email deliverability is and how to improve it in your marketing emails.

What is email deliverability?

Email deliverability, or 'inbox placement', is the ability of emails to reach their intended recipients. Email spam filters block a lot of marketing emails from email inboxes, instead diverting them into spam folders and trash bins. Emails with a higher deliverability rate are more likely to finish their journey in customer inboxes, which means that users are also more likely to read the emails, find out more about your brand and potentially register online, purchase your products or engage in another way.

There are many ways to improve deliverability in an email marketing campaign, and the most common methods involve building the credibility of your organisation and the emails it sends out. It's possible to build credibility by developing the infrastructure of your email marketing system, improving your company's reputation and only sending out high-quality, useful marketing content. Optimising your emails for better deliverability rates is an effective use of time and resources if your organisation relies upon email marketing to chase new leads.

Related: What is email marketing? (Tips on how to launch a campaign)

How to improve inbox placement

Inbox placement is key in determining how successful an email marketing campaign is. It's essential that marketers understand what deliverability is and how to improve it. Follow the steps below to improve deliverability in your email marketing campaign and ensure that the majority of your marketing emails reach their intended recipients:

1. Build a strong sender reputation

The first step to improving the deliverability of the emails you send out is to build a strong sender reputation to pass email reputation checks. If spam filters identify your email address as unethical or potentially a scam they are much more likely to send your marketing emails to spam folders. The emails you send out and their bounce rate impact your organisation's sender reputation. Only send your emails out to customers who want them, because if a customer marks your emails as spam this can seriously impact their deliverability rate.

Be consistent with the volume of emails you send out, following a regular pattern such as once or twice weekly, to avoid spam filters. It's also useful to keep your bounce rate low. Bounce rate refers to the number of emails that don't fail to reach their recipient at all, usually because the email address doesn't exist. Marketing emails with a high bounce rate are much more likely to end up in spam folders, so it's essential to regularly clean your mailing list out.

Related: How to collect email addresses easily for marketing campaigns

2. Use proper authentication

Proper authentication is key to differentiating yourself from spam senders who use deceptive tactics such as email sender spoofing to mimic authentic accounts. If you send marketing emails from your organisation's own ISP address, email filters are less likely to mark them as spam. If you partner with an email marketing company that sends out marketing emails for you, proper email authentication is essential. This tells popular email platforms that your email is authentic and is not the victim of email sender spoof tactics.

There are many different ways to authenticate an email address to maximise deliverability. Use SPF (Sender Policy Framework) to validate your email address. Using SPF also prevents spam senders from sending spoof emails from addresses that mimic yours. You may also want to use DKIM (Domain Keys Identified Mail) to verify your ownership of an email message. When you set DKIM up properly, all of your emails contain an encrypted digital signature that verifies their authenticity. Combining SPF and DKIM offers the best results in terms of inbox placement.

Related: Professional email ID examples for business addresses

3. Develop a successful email infrastructure

Email infrastructure impacts the deliverability of your emails because it impacts the quality of your emails, open rates and sending schedules, and all of these factors impact how likely spam filters are to mark your emails as spam. Your email infrastructure includes the IP address that you send emails from and low-level protocols that your marketing emails adhere to. It's possible to set up a successful email infrastructure yourself, or you might pay a dedicated company to do this for you.

The first decision you may want to make is whether to send your emails from a dedicated IP address or a shared IP address. Dedicated IP addresses are usually best practice for email accounts that send out a high volume of emails, while shared IPs are suitable for smaller email marketing campaigns. Setting up a feedback loop service that helps monitor feedback on your marketing emails, such as when a recipient marks your email as spam, is also essential. This helps you to understand how successful your emails are and how your readers respond to them.

Related: How to write a gentle reminder email

4. Write high-quality content

Email content is one of the biggest factors that affect deliverability. Once you've set up an email infrastructure and authenticated your accounts, it's essential to keep the quality of your emails high. Email providers and spam filters look for similar signs that your emails are authentic and safe. The three biggest factors that might affect how filters classify your emails are language, links and content length. Use positive and professional language in your emails, only link to safe websites and send emails around 500 characters in length. Emails that are too short or too long may alert spam filters.

When you're writing content for marketing emails, aim to create content that's genuinely relevant and useful to your readers. Ask yourself whether the email you're sending answers any of your subscribers' questions or aligns with their expectations from your brand. The design of your emails also factors in. Recipients are more likely to accept and read emails with consistent design and layout each time. It's also essential that your email looks good on mobiles and laptops. Sending out emails with high-quality content reduces the chances of subscribers marking your emails as spam.

Related: How to write a marketing message (including examples)

Tips for improving inbox placement

There are other ways to improve the deliverability of your emails to maximise the number of emails that reach your subscribers' mailboxes. These techniques might not directly improve deliverability, but they reduce the chances of readers marking your emails as spam and have additional beneficial effects, such as increasing engagement and conversion rates. Below are four additional ways in which to boost the deliverability of your marketing emails.

Segment campaigns by audience

Emailing your subscribers with relevant content that they want to read significantly reduces the number of times that readers mark your emails as spam. A simple way to ensure that you only send relevant emails to your subscribers is to segment your mailing list by the audience. This is particularly important for larger organisations with large mailing lists. For example, if you are sending out marketing emails for a clothing brand, you might send women's clothing emails only to those subscribers who have purchased women's clothing before.

Related: Everything to know about email automation

Make it easy for readers to unsubscribe

It might sound counterintuitive to make it too easy for your readers to unsubscribe from your mailing list, but it's always better if readers unsubscribe than mark your email as spam. If you hide unsubscribe buttons at the bottom of your emails, users might lose patience with your organisation and mark your emails as spam instead. Even if only a small percentage of your subscribers mark your emails as spam, this could massively impact your deliverability rate.

Related: Digital marketing skills: definition and examples

Use an email address that accepts replies

Many email marketers use 'do not reply' email addresses to send out marketing messages to their customers. This might make sense when sending out very, very large volumes of emails, which means your company can't respond to all of the potential replies, but for smaller email marketing campaigns, it's better to encourage your subscribers to reply. Using an email address that accepts replies encourages customers to get in touch and boosts your deliverability rates.

Related: 15 digital marketing certifications for online marketing

Use double opt-in for your mailing lists

Email marketers require that subscribers opt-in to receive messages from their mailing list. This usually involves ticking a box on a registration form and giving their email address on a website, and this is a single opt-in. Double opt-in requires a further step, usually requesting subscribers to verify their email address by clicking on a link sent to that address. Requiring double opt-in reduces the number of non-existent email addresses on your mailing list, which in turn keeps your bounce rate low.


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