UK Elections 2017: Which Party is King of Email Deliverability?

The UK general election is just two weeks away, and campaigning is in full swing! With email being used to communicate with voters, it’s a great opportunity for us to pick apart each political party’s email program and see how they are using this channel to win votes.

In a 3-part series, I’ll review performance against a range of deliverability and subscriber engagement metrics to identify the best (and worst) performing programs. I’ll conclude the series with a bold prediction of what the election results will look like based on our email intelligence.

First, let’s evaluate deliverability. For our methodology, we signed up for all political parties’ email programs, in order to assess the email welcomes the parties individually set up. On top of this, we also utilized our Inbox Insight tools to mine the parties’ email data.

Each party’s email program will play a vital role in persuading supporters to volunteer their time, donate funds, and cast their vote, so it’s no surprise that getting their emails delivered will give each of them an immediate advantage.

Based on the past 30-days deliverability performance for the major political parties looks as follows:

It appears that the Greens and Liberal Democrats are achieving above average inbox placement rates, while the Conservatives and UKIP are both underperforming – the latter badly so!

So, what are the key factors that differentiate the high performers from the also-rans?

1. The sign up process
The user experience when a new member signs up goes a long way toward setting the tone for the subsequent relationship between sender and receiver. The key to this is the welcome process, with each party’s approach ranked below.

Only the Greens have a double opt-in (DOI) model, meaning new members need to receive a confirmation email, with an activation link that has to be actioned before the subscription becomes active.

It’s interesting to see that the Green Party is the only party to use this model. DOI ensures a valid email address has been supplied, and is considered best practice—their lists are widely acknowledged as more engaged and responsive.

Most of the other email programs send a welcome email. The Lib Dems example is particularly effective, thanking new members for signing up, encouraging them to engage through social channels, complete their profile, and join the party.

Remarkably, no welcome email was received from the Conservatives or the SNP.

2. Email address quality
The quality of a subscriber’s email address is also important. Every email program wants to maximize the primary addresses they acquire, and for a very good reason! These are subscribers’ preferred addresses–the ones they log into every day and open most of the emails that are delivered. Providing a primary address reflects trust between recipient and sender. Our analysis indicates the percentage of primary addresses in each sender’s list:

It’s worth noting that 99 percent of the reads come from primary addresses. On average each program could strip out 1/6 of their broadcast volume without any negative impact on response, significantly improving deliverability.

3. Authentication
All trusted senders should employ one or more forms of email authentication. Sender Policy Framework (SPF), Domain Keys Identified Mail (DKIM) and Domain-based Message Authentication, Reporting & Conformance (DMARC) flags the sender as legitimate and that content has not been tampered with. This is important as mailbox providers such as Gmail now make this visible to subscribers, with a “?” replacing the logo/avatar when authentication is not in place. This question mark could be the difference between a subscriber pressing open or delete! Generally speaking, the political parties all perform well against this requirement. While the additional use of DMARC by the Greens and Lib Dems won’t have a direct impact on deliverability, it does act as a signal of which email programs are most invested in adherence to email best practices.

4. Volume and frequency
Now let’s take a look at the volume and frequency of each party’s emails–both of which influence deliverability. Higher volume/frequency senders can struggle to achieve good inbox placement rates if subscribers don’t feel the emails are relevant or engaging. Below, I’ve managed to show the level of activity each political parties’ email programs have generated so far:

As you can see, Labour has the largest email list and is also generating the most email activity. The Conservative party’s list is less than half the size of Labour’s, and activity is also lower with an average of 2 emails per week compared with Labour’s 3. This may reflect the Conservatives’ larger war chest, with more funding being directed toward (more expensive) social media channels.

5. Complaints
Subscriber complaints are, perhaps unsurprisingly, one of the biggest influencers of email deliverability. This chart shows how the political parties perform against this metric–with an interesting result!

UKIP clearly stands out head and shoulders above the other programs–thanks largely to a disastrous “Is there a Brexit without UKIP?” campaign.

We have a hypothesis that many members of the UKIP list are actually floating Tory supporters, and this email provided them with a perfect opportunity to remove themselves. Probably not what the UKIP party was aiming for! That said, any high-performing email program should be generating a maximum 0.1 percent complaint rate, and nearly all the programs are well above this threshold.

6. Engagement
How subscribers engage with emails also plays a part. In fact, many of the major mailbox providers now consider subscriber engagement as an additional deliverability factor, and inbox placement rates will be higher when engagement is positive. We will cover engagement in greater detail in part 2, but in the meantime, I can reveal engagement at the top-level by showing the average read rate each program is achieving.

SNP subscribers are clearly highly engaged with their election campaign emails, while the same cannot be said for UKIP! The Greens and Lib Dems are also achieving above average Read rates, with the Conservatives and Labour slightly below.

Pulling it all together
Each of the factors we’ve described have an impact on email deliverability, but it is particularly interesting to see how they operate together. To illustrate this, I have graded each program against each factor, awarding rankings of “above average” (3 points), “average” (2 points), “below average” (1 point), or not present (0 points). This produces the following table:

We can see there is a strong correlation between the resulting weighted scores and inbox placement rates, with the higher scoring programs achieving better deliverability, while the reverse holds true for the lowest scoring programs. Addressing these identified shortcomings will enable political email programs to significantly improve performance, which will generate very real benefits in the form of more volunteering, more donations, and more votes on Election Day.

Next time, I will review the subscriber engagement metrics these programs are generating, identify who the winners and losers are, and what tactics the most engaging emails are using to drive success.


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