The email design principles that outlast every tool

Every year someone publishes a piece titled "Email design trends for the year ahead." Every year that piece is largely wrong within eighteen months. This is not a fault of the writers — email design trends really do change, and the mail clients themselves change what they support, and what looked cutting-edge in one year looks dated by the next.

What does not change, in my experience, is a small handful of underlying principles. Five of them, roughly. They were true when I first started paying attention to email design, and they are still true now, and they will still be true when whatever is fashionable this year is out of fashion next year.

One: text-first, always

Every email should be readable and useful with images turned off. Not just readable in a formal sense — actually useful. If your promotional email is a single large image with a "shop now" button on it, and the subscriber's email client has images off by default (many corporate ones do), that subscriber sees a blank rectangle with a button.

The principle is: images are the decoration, text is the message. When images fail, the email should still work. If you have to test this by disabling images in your own client and re-reading your last three campaigns, do it. You will find things.

Two: one narrow column, not many

The three-column newsletter template is dying, and has been for a decade, and yet keeps showing up in the defaults of every email tool. It looks good in the tool's preview. It looks fine on a laptop. On a phone, which is where the majority of email is now read, it either collapses into an unreadable pile of stacked blocks or asks the reader to pinch and zoom.

The principle is: one column, narrow enough for comfortable reading, works on every device. Multi-column layouts add a whole category of failure modes and remove none. Unless you have an unusually specific reason to use columns, do not.

Three: one hierarchy per email

When someone opens your email, their eye needs to land somewhere first. That first landing spot needs to be the most important thing in the email. Everything else needs to visibly matter less. This is basic visual hierarchy and it is remarkable how often it is broken.

The most common failure: an email with three "primary" buttons, all the same colour and size. Which one is the reader supposed to click? The one they click first. Which one is that? Unknown. The email has abdicated the decision, so the subscriber makes a slower, worse one.

Four: system fonts, or none

Custom web fonts work in most mail clients now, but not all. If you set your body copy in a custom font, roughly ten percent of your subscribers will see a fallback, and the fallback is often nothing like what you intended. Meanwhile you have added kilobytes to every send and a rendering failure mode you cannot see on your own screen.

The principle is: use the fonts that ship with every device. Georgia is on every device. Times is on every device. Helvetica or Arial or the platform-native equivalent are on every device. These fonts were designed to be read at small sizes on small screens. Use them and stop worrying.

Five: whitespace as content

The one design element that has aged the best in email is generous whitespace. Emails with tight, dense layouts read as pressured. Emails with room to breathe read as considered. This is a taste judgment more than a technical one, and it is the hardest of the five principles to argue for because it produces no immediately measurable metric.

What it produces is a small compound effect over time — subscribers who consistently see well-spaced emails come to associate the sender with restraint, and restraint is one of the qualities that separates senders who feel like publishers from senders who feel like broadcasters.

The five principles are all forms of the same underlying idea — do less, but do it deliberately. Everything I still like about email design is downstream of that.

The tools will change again

The tools will change. The templates will change. The mail clients will add and remove features. Interactive email, AMP, dark mode support, animated headers, embedded video previews — all of these come and go in cycles. If your design programme is built around the current cycle, it will need to be rebuilt in three years.

If your design programme is built on the five principles above, or your own version of them, it will not.