Images can make an Outlook signature look professional, but they need to be sized and inserted correctly. Oversized logos bloat every message, and linked images or blocked remote content can appear broken to recipients.
Does this affect you?
Use this for Outlook for Microsoft 365, Outlook 2021, Outlook 2019, Outlook on the web, and Outlook mobile if you need a logo, photo, or social icon in an email signature.
Add an image in desktop Outlook
Resize the file before inserting it. Outlook is not a good image compressor.
- Resize the logo or headshot to about 300 pixels wide or smaller using Windows Photos, Mac Preview, or another editor.
- In Outlook for Windows, open File > Options > Mail > Signatures. On Mac, open Outlook > Settings > Signatures.
- Select an existing signature or create a new one.
- Click where the image should appear in the signature box.
- Click the picture icon in the editor toolbar.
- Choose the resized image file and insert it.
- If needed, drag a corner handle to resize further. Use corners so the image does not stretch.
- Save the signature.
If recipients see a broken image, Outlook may have linked the file or their mail client may be blocking images. Inserting through the signature editor normally embeds the image in the message.
Add an image in Outlook on the web
Web Outlook has separate signature settings from the desktop app.
- Sign in at Outlook.com or Microsoft 365 web mail.
- Click the gear icon and open Mail > Compose and reply, or search for signature.
- Click inside the signature editor.
- Use the image icon in the toolbar.
- Choose the image file from your computer.
- Resize with a corner handle if needed, then save.
More control
Desktop and web signatures may not sync
A signature created in Outlook on the web may not appear in desktop Outlook, and the reverse can also be true. Set it up in each place you send mail from.
Use a small table for alignment
For a logo beside contact details, insert a simple one-row, two-column table. It holds alignment better than spaces or tabs across email clients.
Keep signatures lightweight
Avoid stacking a logo, large headshot, and many image icons. Heavy signatures slow sending and raise the chance that filters strip or block parts of the message.
Check mobile separately
Outlook for iPhone and Android has its own Settings > Signature area. iOS may support richer signatures; Android support can be more limited and often plain text.
Send a test message
Send to a personal Gmail, Outlook.com, or other external account so you can see what recipients actually receive, not just what Outlook previews.
Sources
- Microsoft Support – Create and add an email signature in Outlook (2025)
- Microsoft Support – Add a logo or image to your signature (2025)
- Microsoft Support – Set up email signatures in Outlook on the web (2025)