Gmail Signature Image Not Showing: 5 Real Causes and How to Fix Each

Updated June 2026

You add a logo or headshot to your Gmail signature, it looks fine in the editor — then it vanishes. Sometimes it disappears from the settings page itself; sometimes it shows for you but recipients get a broken-image icon. Those are different failures with different fixes. Five causes account for nearly all of them.

1. The image isn’t at a direct, public HTTPS URL

A Gmail signature doesn’t store your image — it stores a reference to it. Every time anyone views your email, their client fetches the image from that URL. So the URL has to be public, served over HTTPS, and point at the actual image file.

This rules out more than you’d expect:

• Local file paths (C:\Users\... or file://) only ever existed on your machine.
• Google Drive share links are the most common trap. A Drive “anyone with the link” URL points to a viewer page, not the raw image, and Gmail doesn’t reliably hotlink images from Drive. There are URL-rewriting workarounds floating around (drive.google.com/uc?export=view&id=...), but Google has broken them before, and threads on Google’s own support forums report public-view Drive links failing in signatures even with correct sharing settings. As of June 2026, treat any Drive-based approach as unreliable.
• Dropbox and similar share links have the same viewer-page problem.

The test: paste your image URL into a private/incognito browser window. If the browser shows the image and nothing else — no page around it, no login prompt — the URL will work in a signature.

2. Pasting stripped the image

If you copied a signature out of Word, Google Docs, or some web-based generators, the paste may keep the layout but drop the image, or replace it with a reference Gmail can’t resolve. The signature looks complete in the settings box and then degrades on send.

The fix: don’t rely on the paste to carry the image. Place your cursor where the image belongs, click Gmail’s Insert image toolbar button, choose Web Address (URL), and paste the public URL from step 1. Images inserted this way survive saving and sending.

3. You never clicked Save Changes

Gmail’s signature editor does not autosave. The Save Changes button sits at the very bottom of the long Settings page, well below the signature box, and it’s easy to edit, close the tab, and lose everything.

While you’re there, check the Signature defaults dropdowns just under the editor — “for new emails use” and “on reply/forward use.” If either is set to No signature, your signature (image and all) silently won’t appear in that context. And note that the Gmail mobile apps have a separate, plain-text mobile signature setting; if it’s enabled, it replaces your rich signature on mail sent from the phone.

4. The recipient’s client blocks remote images

Sometimes everything on your side is correct and the image still doesn’t show — for them. Many email clients block remote images by default until the reader clicks “download pictures”; corporate Outlook deployments are the usual culprit. Mail between Gmail accounts generally displays images automatically through Google’s image proxy, but you can’t control what the other end uses.

What you can control is the fallback: alt text. An <img> tag with a descriptive alt attribute (“Jane Doe, Acme Co.”) keeps the signature legible while images are blocked, instead of showing an anonymous broken-image box. Explicit width and height attributes also stop the layout from collapsing while the image is missing.

5. Gmail strips base64-embedded images

Some signature generators embed the image directly in the HTML as a base64 data URI (<img src="data:image/png;base64,...">). It feels self-contained, but Gmail doesn’t render base64 images in signatures — they’re dropped or shown broken. Base64 also inflates the markup enormously: a modest logo becomes tens of thousands of characters of encoded text, which alone can blow past Gmail’s 10,000-character signature limit and get the whole signature rejected as too long.

The fix is the same as cause 1: a real hosted image referenced by URL. There is no reliable way to embed image data inside a Gmail signature.

Where to actually host the image

How OnceSig signatures avoid all five

The OnceSig editor builds signatures the way Gmail’s renderer expects: images referenced by public URL (you paste the link, the editor previews it so you catch a bad URL immediately), explicit width/height attributes plus CSS dimensions so logos stay sharp on high-DPI screens and the layout holds when images are blocked, styled alt text as the fallback, and table-based markup that stays under the 10,000-character limit. The editor is free to use; a one-time $9 license removes the small credit line from exports — no subscription, no account. When your signature is ready, the Gmail install guide walks through pasting it and — yes — clicking Save Changes.