Add an image to an Outlook.com signature

The short answer

You can add an image to a signature in Microsoft's web version of Outlook through the signature editor in mail settings. The editor includes an option to insert a picture inline, and in many cases you can also paste an image directly into the signature box. For a logo, the image you insert should be a raster export, typically PNG or JPG, made from your master vector file. It should not be the vector file itself.

This article covers one task: getting a logo image into an Outlook web signature in a form that displays reliably. It does not cover the desktop Outlook apps, mobile apps or third-party signature generators, which handle signatures differently.

Where the signature editor is

Microsoft has rearranged Outlook's web settings more than once, so the exact menu labels may differ from what you see. The general route is consistent:

• Open the Settings panel (the gear icon) in Outlook on the web.
• Find the signatures section. It is usually under the account or mail settings, often labelled Signatures or Compose and reply. The settings search box will find it if you type "signature".
• Create a new signature or select an existing one to edit.
• Place the cursor where the logo should appear and use the insert-picture control in the editor toolbar, or paste a copied image.
• Resize the image if needed, choose whether the signature is added to new messages and/or replies and forwards, then save.

Gap in the evidence: no confirmed, current documentation was supplied for this article. The menu names, any file-size limit on signature images and the exact toolbar wording above are not verified. Check them against Microsoft's own help pages if precision matters.

Why the vector logo is not what goes in the signature

Logo packages usually include a vector master (AI, EPS, PDF or SVG) alongside raster files. Vector artwork scales cleanly and can be edited. Email is a poor place for it, though, because support for SVG across mail clients is inconsistent. Outlook's signature editor is built around common web image formats. In practice, the vector file is your source and a raster image is what you deliver into the signature.

File type | Role in a signature workflow | Notes

AI, EPS, PDF | Source artwork | Open in a vector editor to export a signature-sized image. Not inserted into email.

SVG | Source artwork or web asset | Displays unreliably in email clients, so export to raster for signatures.

PNG | Preferred signature image | Supports transparency, which suits logos placed on white or dark message backgrounds.

JPG | Acceptable signature image | No transparency. Better suited to photographic content than flat logo shapes.

A file extension alone does not tell you whether the artwork inside is genuinely vector. A PDF or EPS can contain nothing but an embedded raster image, and an SVG can wrap a bitmap. If the logo looks soft or pixelated when you zoom in on the source file, it may not be true vector. In that case, exporting a sharp signature image may require the original artwork from whoever created it.

Preparing the image so it displays well

• Export from the vector source at the size the logo will appear, or somewhat larger. Exporting larger helps it stay crisp on high-density screens. Then scale it down in the editor if needed.
• Use a PNG with a transparent background unless your brand guidelines specify a background colour.
• Check the logo against both light and dark backgrounds, since some recipients read mail in dark mode and a dark logo on transparency can disappear.
• Keep the file reasonably small, because a large image adds weight to every message you send.
• Send a test message to yourself and to an account on a different mail service to see how it renders.

Images inserted into a signature are typically sent with the message rather than loaded from an external server. Recipients' mail clients may still block images, show them as attachments, or scale them differently. A signature should therefore stay readable as text even if the logo does not load.

Permission to use the logo

Having access to a logo file is not the same as having permission to use it in a signature, recolour it, crop it or set it alongside other text. If the logo belongs to your employer or a client, follow their brand guidelines. These often set minimum sizes, clear space, approved colour versions and whether the logo may appear in personal email signatures at all. Fonts included in a logo package carry their own licences, and the logo itself may be a registered trademark. Using a logo you do not own or represent in your signature can misrepresent your affiliation.

What remains unconfirmed

This guide is based on general, verifiable principles of email signatures and logo file handling rather than tested, documented specifics. The following were not confirmed: current Outlook web menu wording, any maximum image size or file size for signatures, and how particular recipient mail clients render signature images. Treat the steps as orientation and confirm the details in your own account.