Why You Can't Afford Email Bounces In 2024

‘Bounces’ are tied to email deliverability, which every marketer needs to understand – especially in light of recent news about Gmail and Yahoo actively working on filtering spam from users’ inboxes. 

When you send emails to invalid or lapsed email addresses, you’ll ‘bounce’. Not only will this mean wasting time, but it could also impact your wider sender reputation and, ultimately, your brand’s overall email marketing performance. 

Email Service Providers (ESPs) see email bounces as an early sign of email sender issues because they highlight poor-quality email list management. With that in mind, it’s important to keep track of your bounces and take action accordingly. 

Fortunately, there are steps you can take to minimise bounces and keep your email list working for you. In this guide, we’ll discuss why email bounce back matters and the impact it can have on your overall email marketing performance.

What is an email bounce?

An email bounces when the recipient’s server rejects it and sends it back to you. 

There are two common types of email bounce:

• Hard bounces: This happens when an email address can no longer accept emails, typically when the account no longer exists, or you have been blocked by the ESP. 
• Soft bounces: This is typically caused by a temporary issue, like the recipient’s inbox is full. 

Both types of email bounce matter and require action. However, hard bounces should be your priority – you need to filter them out as soon as possible, as they are permanent issues. Later in this guide, we’ll share our top tips for tackling both hard and soft bounces and maximise email delivery rates.

What’s a good email bounce rate?

Your email bounce rate should be as close to 0 as possible, but obviously, this isn’t always possible. A bounce rate of 2% or less is generally considered an acceptable benchmark, although that can vary from brand to brand. If you practice good list hygiene, your bounce rate will be far lower than a competitor who doesn’t update their own lists.

B2B marketing and bounce rates

In the last year, B2B organisations have found it harder to maintain low bounce rates, with delivery rates dropping from 98.1% to 92.1%, according to the DMA’s latest 2024 Email Benchmarking Report. 

Several problems face B2B marketers when it comes to email marketing. Firstly, work email inboxes are busier than ever, and many users manage more than one work email address. 

In addition, B2B marketers are more likely to rent or buy email lists, as GDPR does allow marketers to email contacts at generic email addresses without permission. If an email address is in an individual’s name, however, it is still classed as personal data under GDPR rules. Under PECR, marketers are allowed to email ‘corporate subscribers’ on an opt-out (rather than opt-in) basis, but this does not include sole traders, for example. 

Due to the complexities of GDPR and PECR for corporate marketers, B2B email lists are more likely to include invalid email addresses. 

Another issue facing B2B marketers is the increased influx of spam reaching work inboxes, resulting in the tightening of corporate firewalls for many organisations. In March, TechRadar reported B2B to be the “spammiest” of email verticals with an average spam complaint rate of 2.01% - well above the 0.3% threshold set in Google and Yahoo’s latest updates. 

Both spam and bounce rates should be monitored by marketers, but for those in B2B, this is a priority.

Why do emails bounce back?

Email bounces are normal, but you need to keep an eye on them. If you have had an email list for a long time, inherited from a merger or even acquired data through a bought list, then you are more likely to have high email bounce rates.

Even newer lists can have bounce issues. For example, if you run a campaign that encourages people to sign up for your newsletter to reveal a discount code, you might find people give fake email addresses. You can negate this by sending codes to their email, rather than revealing it in the browser. Double opt-in is also a great solution to this as it ensures every subscriber's details are accurate. The process will likely reduce sign-up by its very nature, but it encourages initial engagement, setting an expectation for readers that you will contact them.  

So, wherever you are on your email marketing journey, you’ll need to get to grips with common causes of email bounces. 

• Incorrect or deleted email accounts: The recipient’s email address no longer or has never existed, this could be due to a typo in their address, or because they have deleted their account.
• Recipient server issues: The addressee’s server is telling us that the email cannot be delivered because of a temporary error, perhaps due to high traffic. If a temporary error code is received, email mail service providers may attempt to resend this email a few minutes later.
• Content related: An email provider soft bounces on the basis of suspicious content. This is different from spam-flagged emails (more on that later), and this sort of soft bounce can be a signal that your sender's reputation is at risk. 
• Sender reputation related: If your emails are repeatedly flagged as spam, this will impact your sender reputation and email providers may start to soft bounce emails before they are even delivered (and ultimately marked as spam).

Not only do bounces directly affect your deliverability rate, but having several bounces on your list will put your entire sender reputation at risk with ESPs.

What’s the difference between spam email bounce and spam complaints?

When an email bounces, it is not delivered to the recipient. The email service provider bounces the email before it has a chance to land in their inbox. When an email goes into spam or junk, it is delivered but then the recipient’s email provider or the recipient themselves has marked it as a spam complaint.

The risks of high bounce rates:

A small number of email bounces is unavoidable, especially if you have a big list. People will delete their addresses, or have full inboxes… this is all part of sending emails. It’s what you do when you notice the emails bounce that matters– this is why bounce rates are one of the key metrics to measure email success. 

Sender reputation damage

This is the biggest issue for senders when it comes to high bounce rates. As a marketer, you will be aware that if an email bounces, then it doesn’t deliver to the recipient, but did you know that a high bounce rate can impact your overall sender reputation with email service providers? Gmail, Yahoo, and other email providers use bounce rates as a signal for sender score and reputation.

In fact, Gmail even highlights the importance of tackling even the smallest amount of bounces in its Email Sender Guidelines:

“If messages start bouncing or start being deferred, reduce the sending volume until the SMTP error rate decreases. Then, increase slowly again. If bounces and deferrals continue at a low volume, review individual messages to identify problems. For example, you can try sending a blank test message and see if it experiences issues.”

This is why it’s important to take a critical look at benchmarks, and actively work to reduce your bounce rate, even if it is consistently below 2%. 

Wasting time on campaigns

If your emails aren’t delivered, your team’s time is wasted. What’s the point of working to deliver a great campaign if your emails aren’t seen by your intended audience? This isn’t just a one-off risk, either; it’s a long-term issue if you notice increasing bounce rates and your sender reputation is impacted as a result.

So, while cleansing your database and reducing the overall number of recipients might feel counterintuitive, this is your first step towards improving deliverability and actively increasing your open and click-through rates.

Lost opportunities

Sending emails only for them to bounce is a massive missed opportunity. You risk investing a valuable marketing budget in email, only for your overall email permanence to be negatively impacted. This is hugely important for in-house marketers who are actively trying to encourage stakeholders to believe in the power of email. 

How to reduce bounce rates (and improve sender reputation)

It’s time for the golden ticket question: how to improve bounce rates? In this guide, we’ve explored at length the risks associated with high email bounce rates, and why it’s important to invest in maximising email deliverability from the outset. But how do you do it?

Here are some steps you can take today to start bringing down that bounce rate, and ensure the highest email deliverability possible. 

Measure sender reputation

We always say that the first step towards success is measurement. How can you even begin to achieve your goals if you don’t know how your emails are currently performing?

By measuring your email bounce rates, and comparing them with your previous campaigns, you will start to notice patterns. For example, if bounce rates increased when you merged lists, this could be a sign of poor-quality data. Additionally, a certain campaign may have triggered a soft bounce if the mailbox provider deemed the content as spam.

If you notice your bounce rate has increased, it’s worth looking at your sender reputation to see if this is the cause. You can find out your sender reputation using Sender Score, which is a tool developed by the email marketing platform and Jarrang partner, Validity. 

Validity also offers a tool to reduce bounces and ultimately improve reputation. BriteVerify will verify your email list and ensure you are only sending messages to legitimate subscribers.

We talk about sender reputation in our dedicated guide to email deliverability. 

Actively cleanse your data

Managing an email database is an ongoing process. As your list grows, you will need to invest more time into managing it and ensuring each subscriber is a legitimate recipient of your content. 

Data cleansing is one way to ensure your email list is in the best condition, and this will help to reduce bounce rates. When an email hard bounces, you should look to remove it from your list as soon as possible. 

Soft bounces may be different. For example, if an email soft bounces, but you can see that the recipient has previously opened and interacted with emails, it might be a temporary issue like their inbox is full or their server is unavailable. Keep an eye on soft bounces, and if they reoccur, then it’s likely time to remove them from your list. 

Feedback Loops (FBLs)

Large volume senders can set up Feedback Loops to identify which email campaigns are triggering bounces and spam complaints from the mailbox provider. A FBL is a line of code you add to your email header, this will then flag unusual spam rates in Postmaster Tools. 

Avoid email ‘bursts’

The frequency with which you send emails will depend on your brand and audience expectations. For example, subscribers expect multiple emails per day from global ecommerce brands like ASOS or Amazon, but most companies are unlikely to be able to email customers that often without seeing repercussions. 

You must also consider the consistency of your email campaigns. Spam senders are more likely to hit a high volume but inconsistently, while legitimate email should come with regularity. 

Try to avoid sending too many emails in a short period of time. If you know you’ll be sending more than usual, keep a close eye on deliverability as the emails land, so you can remove any hard bounces as soon as they happen. This will minimise the impact on your sender reputation. 

Prioritise email personalisation

If you intend to run a campaign to increase subscribers, make sure that they know what to expect from you. How often will you contact them? And what will you talk about? Ideally, give them the opportunity to choose what they will receive and when. 

Put the power in the hands of your subscribers by allowing them to opt into relevant content. This will make them less likely to give a fake email address in exchange for a perk, for example. 

Turn-on double opt-in

Double opt-in means a user has to both tick a box to say they are willing to receive your emails and confirm this approval by clicking a link in an email. This is a fantastic way to maximise email deliverability and actively reduce bounce rates because it means an email has to be delivered and acknowledged before a reader is added to your list.

Experiment with tick boxes for personalisation

This is a strategy that B2B markets, in particular, should take notice of, as it will help to improve those falling delivery rates we mentioned earlier. Tick boxes on registration forms allow users to control what type of content they receive, reassuring them that you will only send relevant emails. 

Focus on quality content

Successful email marketing is about finding the balance between quality and quantity. Every email you send must provide value, and the quality of content should always align with what your audience has come to expect from you. 

Reduce bounce rates and improve email deliverability with Jarrang

Now you can see that your email bounce rate is more than just a figure to keep an eye on– it’s a statistic you need to actively monitor, and invest time in managing. Doing so requires both industry insight, time and technology. At Jarrang, we have all three. 

We work with busy marketing teams to create high-performing email campaigns that help achieve your wider goals. A big part of this is working with your team and our technology partners like Validity to reduce bounce rates and improve deliverability. 

Need help with any of the above? Get in touch today to find out how we can help.