Deliverability for the New Year: Engagement

The challenges for deliverability have changed significantly over the past few years. Just a few years ago it was much harder to ensure that relevant email was successfully delivered to the recipient’s inbox than it is now. It made little difference whether your recipients opened the message or simply removed it without opening it or clicking into it. Being able to estimate results of a campaign in advance was much more of a gamble than it is today.

ISPs were using systems not yet sophisticated enough to accurately differentiate between unwanted mail and legitimate items, resulting in relevant messages going to the spam folder. The methods available to ISPs at the time often resulted in large numbers of false positives when trying to flag spam, usually as a result of using inflexible blacklisting, scanning for ‘suspicious’ HTML formatting and ‘spamlike’ phrasing or relying on IP address history.

Without senders resorting to elaborate, and often time consuming, warm up phases large volume sending was nearly impossible to achieve with any degree of reliable deliverability.

So what are the current challenges for deliverability?

The likes and dislikes of your recipient are now the most important criteria for the ISP with regards to how to classify the email, and by proxy the sender. Through engagement metrics ISPs have greatly improved their SPAM detection capabilities and have reduced the number of false positives, so deliverability is now linked directly with the quality of the message and the selection of the recipients you send to.

BUT: By sending legitimate emails and still ignoring the trend to engage and actively communicate with your subscribers, it could be even harder for you to deliver to the inbox of your recipients.
In light of this the Emarsys deliverability team has put together a few tips that will help with your deliverability in the New Year, especially with regards to engagement and relevancy:

Actively communicate with your subscribers providing them with high quality content

Engagement is key. To expand the size of a contact list is important, but has to almost be secondary to the engagement of the recipients. Marketers need to ensure that the recipients are engaged by providing relevant and quality content, which then is the basis for expanding the list size. Inappropriate or uninteresting content is the fastest way to lose valuable and interested subscribers.

Personalising isn’t optional. Sending mail without customised greeting line, increases the chances of it being reported as spam by your recipients.

Keep content interesting. Make use of your contacts preferences, responses, purchase history and take advantage of all information you hold on your recipients to determine what content they would be interested in. Having a beautifully designed template is important but if the content isn’t something the recipient cares about they will not engage.
Use social media in your emails. Social links can help you connect with your subscribers using a different channel with the benefit of interesting content being shared by the recipients themselves. Make sure that you keep your social profile up-to-date with current stories, links or content, taking care to make the engagement experience for your users as simple and appealing as possible.

Sending Consistency – Setup and Maintain Expectations

Full disclosure! Be honest and provide clear information on what a contact is signing up to when they register their interest and subscribe to you. Clearly explain what kind of messages they can expect, and what the value of the mail will be to them to avoid disappointed recipients unsubscribing or worse, flagging your mail as spam. Having some sample emails (e.g. newsletter archive) on your website is recommended so that users can see what they are signing up for in advance.

Offer varied send frequencies. Providing regular content is obvious, but if the recipients are provided with options as to how frequently they want to receive content then you will be much more likely to have better response rates when you send email.

Try not to change the sender name and address as this will impact on your response rate, and possibly confuse recipients or interfere with the deliverability of your mail. Recipients often add senders to their address book to ensure that images are correctly displayed, etc. which is something you should encourage if you do not already do so.

List Maintenance 1: Avoid Spam Traps and Hard Bounces.

A poor quality list will cause a variety of deliverability problems from blacklistings through spam traps, to a bad reputation through too many hard bounces (invalid email addresses). If your list contains spam traps – email addresses created for the purpose of luring spammers – your deliverability will suffer.

Spam traps are divided into two categories: Pristine and Recycled. Both are geared to do the same thing: identify, flag and possibly block spammers.

Pristine spam traps are addresses that are specifically created to be picked up by spam bots, so if one of these addresses is on your list then it will usually result in your sending IP and/or domain being blacklisted.

Recycled spam traps are email addresses that have been active email addresses at one point in time, possibly with valid permission to receive content. They have gone dormant or inactive, and they’ve been taken over by the ISP after a period of inactivity (usually 6-12 months) to be reused as spam traps. This is one of the reasons why a regular hard bounce cleanup is so important – to avoid invalid email addresses turning into spam traps, which are now deliverable again!

Protect your registration form. Registrations made too easy are open to misuse by bots to register randomly generated addresses or even worse, spamtraps. Using acquired, shared or rented lists has the same danger so it is, generally speaking, best to avoid all third-party email address acquisitions.

Making sure that you do regular hard bounce clean-ups will help remove invalid email addresses before they have a chance to be turned into a spam trap, underlining the need for regular and thorough list maintenance. If you have a database which has too many addresses in that bounce, are invalid, cause complaints or have users that don’t open their mail, then your chances of successfully delivering to an inbox will be low. A database cleaning system is therefore a must!

List Maintanance 2: Beware inactive subscribers.

Inactive subscribers make for a dangerous grey area, and pose a huge risk to any sender as they hurt deliverability by bringing down your response and reputation ratings. Marketers often make the mistake to counter the reputation loss by adding even more recipients to the send pool by using third party lists (bought, shared or rented) as well as sending to old contacts to reactivate them. Looking at it rationally there is no way that this will improve matters as trying to force response and revenue by just sending more only will make reputation rates worse and much harder to fix. The result will be ISPs starting to block senders based on the average recipients reactions.

Non-responsive, inactive users need to be removed from your lists regularly because:

  • They adversely affect your response rate and subsequently reputation.
  • Passive disinterest indicates that recipients do not want your emails, and will be more likely to report content as spam if you keep sending it to them.
  • The address may have been turned into a recycled spam trap.


Defining ‘Active’ or ‘Inactive’? ISPs check to see whether the email has been opened, deleted, marked as spam, marked as ‘not spam’, and so on. Marketers on the other hand do not have access to the same metrics but can get a good overview of their reputation by looking at other data such as opens, clicks, conversions or webshop traffic generated. Even if ISPs do not disclose their exact rates, there is enough data available to you to assess which recipients are active or not.

Inactivity is often ignored, but shouldn’t be. If inactive addresses are ignored for long enough they will become complainers, unknown users (hard bounces) or spam traps. There are other reasons for not regularly sending to inactive recipients: An unnecessarily large list containing too many non-responders can also cause lag in the delivery time that affects active users as well. Larger queues with bad reputation volume lead to more throttling by ISPs. This is a problem for time sensitive emails and especially during times, like Christmas, when the ISPs are facing unusual high volume from all senders.

A good starting point would be to stop sending regularly, especially if you send multiple times per week for all recipients who showed no activity over a period of several months even though they have been receiving these emails. When selecting for inactivity try different time frames of inactivity (6, 9, 12 months, etc.). A longer timeframe of inactivity used for selection of inactive users will ensure that the list isn’t reduced too much too soon, so we would advise to start with a longer timeframe and then reduce the timeframe down in increments until you have reached the desired results.

There is no universal rule of thumb, each situation is different so it is better to start small and reduce incrementally to avoid losing contacts who might be ready to reengage later on. Before completely purging the inactive contacts you can try to engage them one last time by sending a reactivation email campaign, but do make sure that this is no more than 5% of the total daily send volume.

Dead addresses, recipients who do not react to these reactivation emails should be cleaned permanently, to ensure higher inbox placement rates, increased response rates, and ultimately increased revenues.

Use the following engagement metrics which are available to you as a rule of thumb:

  • Ideally having a Unique Open Rate of above 8% (for stable inbox delivery above 12%)
  • A Hard Bounce Rate less than 1%
  • Spam Complaint Rate should stay below 0.1%


To Conclude

Today, reactivity is one of the most important parameters. If you’ve got a high response rate (opens, clicks, recipients spending time within an email, recipients marking your messages as important) then you will not experience many deliverability issues.

Deliverability now relies more on you tailoring content to the likes of your recipient and by personalizing the messages you can ensure that they engage with the content that is interesting to them. Take advantage of their willingness to interact with social media and include functionality in your emails, whilst making sure that they are always clear on exactly what to expect. Giving them the option to vary the frequency, and keeping contacts off the lists which are not engaging will help keep your reputation good, and will ultimately benefit your ROI.

In order to deliver, you have to be relevant. It’s as simple as that. Relevance leads to better response rate and engaged recipients which is the basis for modern deliverability.

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Wednesday, 12 December 2012