Images Not Showing in Email: What to Check and How to Fix It
Seven reasons your recipient sees empty rectangles
Mailvex · 31 August 2026 · 4 min read
If your recipient sees empty rectangles instead of images, there are seven possible causes. The most common needs no fixing at all: many email clients block images by default and only show them after someone clicks to load. The other six are mistakes in addresses, access or file weight, and all of them take minutes to correct.
First things first: often nothing is broken
Before hunting for a fault, check the obvious: open the email in a different client. If images appear in Gmail but not in Outlook, the issue is your recipient settings rather than your email.
Blocking images by default is standard practice for corporate mail systems and older Outlook versions. It exists for security: an image in an email can tell the sender that the message was opened.
Which means part of your audience will see the email with no images at all, no matter how correctly you built it. The email has to stay comprehensible that way.
Seven causes and what to do
If nobody sees the images rather than only some people, one of six technical causes applies. Here is each of them.
| Cause | How to check | What to do |
|---|---|---|
| The client blocks images | open the email in Outlook or corporate mail | add alt text, do not hide meaning inside images |
| A relative link | look at the address: does it start with http | replace with a full https address |
| Image on private storage | open the image address in a private browser window | move it to public hosting |
| Hosting requires a login | the address returns 401 or 403 | use a direct link with no sign-in |
| The image is too heavy | check the file size | compress to 200KB, JPEG or WebP |
| Broken link | the address returns 404 | check every address before sending |
| Source domain blocked | the image exists but fails for some people | host it on the same domain as your site |
Work through them top to bottom: the earlier causes are the more common ones.
Alt text solves half the problem
Alt text is what appears in place of an image that did not load. It is neither a formality nor a checkbox: for part of your audience it is the only thing they will see where the picture should be.
Write it meaningfully. Not "image" or "banner" but what the picture would have said in words: "30% off the whole collection until 15 March".
- describe the content, not the fact that an image exists
- if there is text in the image, repeat it in the alt text
- for decorative images leave the attribute empty rather than inventing a description
- set the colour and size of the alt text, or it renders small and grey
- specify image width and height so the block does not collapse
The last point matters more than it looks. Without stated dimensions a block holding an unloaded image shrinks to a thin strip and the layout falls apart.
The rule that always saves you
The rule is simple: the email must work without images. That does not mean abandoning them — only not placing meaning on them that the email cannot survive without.
In practice: the main offer, the discount, the deadline and the button belong in text rather than inside a banner. Images reinforce, they do not carry information alone.
One more consideration. Most emails are opened on phones, often on a weak connection. Heavy images do not finish loading before someone closes the message, even when everything is configured correctly.
How to check before sending
Before sending, turn off image loading in your own mail client and open the test message. You will see exactly what part of your audience sees.
- the copy reads without images
- alt texts are meaningful, not "image1"
- blocks have not collapsed — dimensions are set
- every image address starts with https
- every address opens in a private browser window
- each image is under 200KB
How a builder handles this
In Mailvex images upload to dedicated storage and get permanent direct addresses — relative links and private storage cannot happen by design.
Alt text can be generated from the image content, and dimensions are set automatically when a block is inserted. The validation panel flags images without alt text before export.
Build an email that reads without images.
Browse templatesFrequently asked questions
Why do I see the images but my recipient does not?
Most likely their client blocks images by default — corporate systems and older Outlook versions do this. It is a setting on their side rather than an error in your email. Make sure the email stays comprehensible without images.
Can I embed an image inside the email so it cannot be blocked?
Technically yes, an image can be encoded as text and embedded in the email code. But most clients do not display such images, and the email weight multiplies, potentially crossing the clipping threshold. In practice this approach does not work.
What image weight counts as normal?
Under 200 kilobytes per image and under 100 kilobytes for the whole email excluding images. Remember that emails are read on phones on any connection: a heavy image will not finish loading.
