15. Length and Size of the Email Message


The optimal length for email messages can vary dramatically based on your objectives, audience demographics, the type of content, frequency, the competitive environment and other factors.

For example, subscribers receiving a monthly newsletter would expect it to be much longer than a daily or weekly one. A grand opening or seminar invitation is typically going to be very short, whereas a B2B newsletter discussing strategic and thought-provoking topics can easily run the print equivalent of 4-6 pages.

If the email message need to be longer than a more, provide an index of the articles, categorize them into sections, and provide details later in the body of the message.

The objective should be to create the retention of the subscriber in locating the relevant and interesting topics easily and moving directly to the location in the message to read the details.

Don’t be too concerned with message size. There is no data to support any negative effect on performance from messages above 50 KB, for example. Having said that, you should still try to keep message size to 40 to 50 KB, because some recipients might have size limits in the email client or receiver email server settings. To keep the HTML message sizes to less than 40 to 50KB, would require the images to be hosted on the email server itself or an external hosting place, that is capable enough to serve the images quickly and to a large number of concurrent requests that may be coming from opening subscribers.

Read earlier blogs on the subject “Guide to a Better HTML Email Design” on Kenscio Blog.