Images Off by Default

What some readers actually see

Mail clients vary in whether they load images automatically, and a proportion of readers see a message with every picture replaced by an empty box or a filename.

That includes people with images disabled deliberately, some corporate mail systems, some clients by default, and anybody on a poor connection where images fail to load.

For a message built as a designed layout with the offer in a graphic, those readers see almost nothing.

The proportion is not enormous and it is not negligible, and the cost of designing for it is close to zero.

The failure mode

Specific and common enough to be worth naming.

A business creates a message in a template with a large header image, a banner containing the offer, and a button which is itself an image.

With images off, that message is three empty boxes, some legal text at the bottom, and nothing else.

There is no offer, no explanation, and nothing to click, because the clickable element was a picture.

The reader sees a broken message from a business that sends broken messages, and the next one is less likely to be opened.

The rule

• Every important word exists as text.
• The main action is a text link or a styled button.
• Images support rather than carry.
• Alt text on every image, saying something.
• The message reads with images removed entirely.

The second matters most commercially: an image button is invisible when images are off, so the one thing you wanted somebody to do disappears.

Alt text is the fallback

The part most senders leave empty, and it is the only thing shown in place of a blocked image.

Write it as what the image communicates rather than as a description of the picture.

For a photograph of finished work, the alt text might be a completed patio in Coquitlam, which tells a reader with images off what they are missing.

For a button, it should say what the button says: book a spring service.

Empty alt text produces a blank space, and a filename produces something worse.

It costs a few seconds per image and it is the difference between a message that degrades and one that collapses.

A worked example

A business sent a seasonal offer built as a single large image, on the reasonable basis that it looked exactly as designed and required no formatting decisions.

Their click rate was a fraction of their usual.

Testing it with images disabled showed one empty box and a footer.

They rebuilt it with the offer as text, a photograph beneath it, and a text-based button, keeping the same wording and the same picture.

Clicks returned to their normal level and slightly exceeded it.

The design had been the reason the message failed, and nothing about the offer or the list had been the problem.

Test it in one minute

The check, and it is genuinely quick.

Send yourself a test, open it, and turn images off in your mail client, which most allow in settings or with a per-message option.

Read what remains and ask whether somebody could act on it.

Do the same test by reading it aloud with the images ignored, which catches the sentences that only make sense with a picture beside them.

Add it to whatever you do before sending, alongside checking the links, and it becomes a habit rather than an exercise.

Dark mode is the same problem now

Worth adding, since it has become the more common way a message breaks.

Mail clients increasingly invert colours for readers using dark mode, and they do it unevenly: some invert everything, some invert some elements, and some leave images alone.

Which produces dark text on a dark background, a logo with a white box around it, or a design that looks nothing like the one you approved.

Test in dark mode as well as with images off, since between them they cover most of how a message reaches somebody differently from how you built it.

Simple layouts survive both. Elaborate ones survive neither.

Simpler messages avoid all of this

The conclusion, and it points somewhere useful.

A message written as text, from a person, with one photograph and a text link, renders correctly everywhere: images on or off, dark mode or light, phone or desktop, any client.

It also reads as correspondence rather than as marketing, which for a small business is an advantage rather than a compromise.

Elaborate templates exist because large organisations need consistency across many senders, which is not a problem a business with one sender has.

The simplest version is both the most robust and the most appropriate, which is an unusually convenient alignment.

Weight matters too

A related consequence of an image-heavy message, and it affects everybody rather than a minority.

Messages built from large images are slow to load on a phone connection, and some clients clip a message beyond a certain size, showing a link to view the rest.

A clipped message frequently loses its footer, which is where the unsubscribe link lives, and that is a problem beyond presentation.

Resize images for the width they will actually display at rather than sending them at full resolution and letting the client scale them down.

A message that loads immediately on a phone is read more often than one that loads eventually, which is the same argument as for a web page.

The counter-case

Images are not the enemy.

For anybody selling something visual, photographs are the message, and stripping them to survive a blocked-image case would remove the point of sending.

The proportion of readers affected is also modest, and designing entirely around a minority case can produce a plainer message that performs worse with the majority.

The argument is not to avoid images. It is that the meaning and the action should survive without them, which costs nothing and rules nothing out.

Use pictures freely, and make sure the message still works when they are not there.

Before sending

1. Put every important word in text.
2. Make the button text rather than an image.
3. Write alt text that says something useful.
4. Send yourself a test.
5. Turn images off and read what remains.
6. Check it in dark mode.
7. Prefer the simpler layout when in doubt.

Step two is the one with a direct commercial cost, since an image button disappearing takes the entire purpose of the message with it.

Getting the files right is covered in compressing images without making them ugly.

Frequently asked questions

West Coast Media Solutions Inc. provides web design, web development, hosting, digital marketing, and business consulting to organisations across Canada, drawing on more than twenty-five years in the field.