Should investment bankers optimize email subject line length?

The average business person receives 125 emails a day. That’s one every three minutes. When I worked at Credit Suisse, I received about double this, so I think it’s fair to estimate that somewhere in the region of 250 emails hit the inbox of a banker each day.

Despite the best efforts of internal messaging applications such as Slack, email volume isn’t dwindling. As a result, most people have become pretty good at making a quick decision about what needs to be read and what can be ignored.

As a banker, every message you send is competing for attention with multiple other messages, even if you’re sending over requested materials, so how can you increase the chances that yours will be opened and not deleted?

The context in which your email is being read, such as the device and schedule of the recipient, can go a long way to your email being opened and acted on. You probably already consider day and time when sending your email, but ever since the introduction of Blackberry phones, the chances of your email being opened on a desktop have steadily decreased.

According to a study by Litmus, 53% of emails are opened on a mobile device. If you know your clients (or your team) are usually on the road and rely on their smartphones to read and answer email, consider this when structuring your message and sending any attachments. For example, PDFs are generally easier to view than PowerPoints, copying and pasting key text excerpts from a word document into the body of an email can make it much easier to review. I always like to word any questions in such a way that they can be answered with a simple “yes” response, or if there are options, list them out clearly to generate a quicker-to-tap response of “option one” or similar.

The length of email subject line is something you can also optimize for. On this opinions tend to fall into two camps: 1. It matters or 2. It doesn’t.

Those that think it matters, argue that six to ten words or 41-50 characters are optimal. Phrasee, an email subject line optimization company (yes, it’s a thing) originally stood on the “it matters” side of the debate, but after conducting its own data analysis and, adjusting for a number of analytical concerns in the studies such as normalizing the data, concluded email subject line length doesn’t really matter.

However, while there may be no real strong analytical support for an optimal email subject line, I would try to keep it to the six to ten word range because it probably sufficiently communicates what you need and also it’s less likely to be truncated by mobile or tablet devices, which tend to cut off subject lines somewhere around 30 characters. Also, if you have a deadline a “need to respond by x” as the subject line can also be effective.

Although these are small optimizations, finding ways to increase your email and response rate, even incrementally, could be a critical link in getting your email opened and ultimately winning more client business.

Are there other areas of communications or emails you’re interested in exploring? Email me at