How to create a signature

  1. Open the Settings → Sending Identities screen.
  2. You will see a list of your accounts. Click the Edit button to access the signature for each account.

If your default message format is set to allow rich text formatting, the signature text box will also be rich text, allowing you to change fonts or colors and add links. You can change your default message format by going to the Settings → Preferences screen.

How to create a signature with an image

You can insert an image into your signature by following these steps. Note: The image must already be available on the internet as a link, as it is not possible to upload a file into the signature editor.

  1. Open the Settings → Sending Identities screen.
  2. Click the Edit button for the signature you wish to change.
  3. Select the Image icon from the formatting toolbar.
  4. Paste your image's URL and click the blue Insert Image button.
  5. Click Save.

Make sure you have permission to use the picture you are linking to. You'll need to think about:

  1. Copyright and fair use limitations. Can I use that picture? is an infographic showing when you can and can't use images.
  2. Bandwidth. When your email is viewed, the recipient's mail client will request the image from the remote web server. If your mail is going to many recipients, the image host may not want you using up their bandwidth.
  3. Unexpected image changes. If you don't own the image on the remote host, the remote server can remove or change the image at any time, causing your image signature to change without you doing anything.

If you wish to host your own image, you can do so by uploading the image to your Files. To do so:

  1. Go to the Files screen.
  2. Click the Upload button and select Upload Files from the dropdown menu.
  3. Select the image file you wish to upload and click Open. Your image has now been uploaded to your Files.
  4. Click on the image file, then click the Share button at the top of your screen.
  5. Select Enable, then click Copy to Clipboard to copy the image URL. This URL can then be used to share the files with others.

We strongly recommend that your image's width be less than 320 pixels. Our system doesn't reduce the size of your image, so the size of the image you load is what people will get every time you email them. If it's wider than 320px, it will probably force horizontal scrolling on mobile, which may not look ideal.

You can test how your signature image looks to mobile users by loading Fastmail on your mobile device, and then opening a new email. If you need to scroll sideways to see the whole picture, the image is too big.

If you are part of a multi-user account, an account administrator will have to upload the files on your behalf and let you know of the website URL to access your image. Remember that images hosted through your file storage in your signature will contribute to your Fastmail download limits.

Alternatively, you may wish to use an image hosting service if your image signature will use a lot of bandwidth.