Choose Icons for an Outlook Signature

The short answer

For an Outlook signature, choose a small, consistent set of simple icons, such as phone, mobile, email, website and the social networks you actually use. Keep each icon as editable vector artwork in your source files, but place raster exports, usually PNG, in the signature itself. Vector formats such as SVG are ideal for designing and resizing icons. Email clients, including several versions of Outlook, do not reliably display SVG inside messages, so a flattened raster copy is the safer delivery format.

In practice you manage two layers. The vector master is where you edit shape, color and spacing. The raster preview is what recipients actually see. Treating these as separate files keeps the signature dependable without losing the ability to update the artwork later.

Vector artwork, embedded raster and raster previews

The distinction matters when you source and prepare icons:

• Vector artwork: shapes defined as paths, usually in SVG, AI, EPS or PDF files. It scales cleanly and can be recolored, so it is the right format for your master icon set.
• Embedded raster inside a vector file: some SVG, EPS or PDF files only wrap a pixel image. They carry a vector-format extension but contain no editable paths, so they will blur when enlarged and cannot be recolored cleanly.
• Raster preview or export: a PNG or JPG generated from the vector master at a fixed size. This is the file that goes into the Outlook signature.

A file extension alone does not confirm editable paths. Open a downloaded icon in a vector editor and check whether its outlines can be selected and adjusted before you rely on it as a master.

What to look for in signature icons

• Simple shapes: fine detail disappears at signature size, so solid, bold glyphs read better than intricate line work.
• One visual family: matching stroke weight, corner style and fill approach make a row of icons look deliberate rather than assembled.
• A consistent bounding box: icons drawn on the same square canvas line up evenly and are easier to space.
• Color that works on light and dark backgrounds: a dark glyph on a transparent background can become hard to see when a recipient views mail in dark mode. A filled circle or rounded square behind the glyph usually stays visible in both modes.
• Only the icons you need: each extra icon adds visual noise and another image that may be blocked or shown as an attachment.

Choosing a mobile icon

If your signature lists both a desk line and a mobile number, use visually distinct icons. A handset glyph usually signals a landline, and a smartphone outline signals a mobile. Pick both from the same icon family so they differ in meaning but not in style. If you list only one number, a single phone icon is enough. Adding a second symbol without a second number only creates ambiguity.

The icon is a visual cue, not a substitute for the number. Keep the number as live text next to it. That way the number stays readable when images are blocked, and phones can still recognize it as tappable.

How icons behave in Outlook and on mobile devices

Outlook exists as several clients: classic desktop for Windows, the newer desktop app, Outlook on the web, Outlook for Mac, and the iOS and Android apps. They do not share identical signature editors or rendering behavior. Support for SVG, how inserted images are converted, whether signatures sync between devices, and how much rich formatting the mobile apps accept all depend on the client and version. Check Microsoft's current documentation for the clients your organization uses. No version-specific documentation was supplied for this article, so these points are general principles rather than confirmed specifications.

• Embedded vs. hosted images: images embedded in the message may appear to some recipients as attachments. Images loaded from a web server may be blocked until the recipient chooses to download them. Either way, design the signature to make sense when icons do not load.
• Alt text: give every icon short, descriptive alternative text, such as the network name or 'Mobile', so blocked or unread images still communicate.
• High-density screens: export raster icons at a multiple of their displayed size and scale them down in the signature so they stay sharp on phones and high-resolution displays.
• Mobile signature settings: the signature configured in a mobile app may be separate from your desktop signature and may support less formatting. Confirm what your app version allows before assuming image icons will carry over.

A practical preparation workflow

• Collect or draw the icons as vector artwork and confirm the paths are genuinely editable.
• Normalize them to one canvas size, stroke weight and color palette.
• Decide whether the icons need a background shape for dark-mode legibility.
• Export PNG files with transparency at a multiple of the intended display size.
• Insert the PNGs into the signature, set the display size and add alt text.
• Send test messages to the Outlook clients and devices you care about, in light and dark mode, with images allowed and blocked.
• Keep the vector masters with the exports so future edits start from the source, not from a flattened PNG.

Licensing and brand rules

Being able to download an icon does not give you permission to modify it or use it in every context. Free and paid icon libraries each set their own terms on attribution, commercial use and alteration, so read the license for the set you choose. Social network logos are trademarks, and their owners typically publish brand guidelines that limit recoloring, distortion or redrawing. If guidelines specify a particular mark, use the official artwork rather than a look-alike from a generic icon pack. The same applies to your own company logo and any fonts used to build custom icons: the artwork, the typeface license and the trademark are separate permissions.

Gaps in this guidance

No confirmed specifications, version numbers or measurements were available for this article. Questions such as exactly which Outlook versions render SVG, the pixel dimensions Outlook recommends, or what the current mobile apps accept in signatures should be checked against Microsoft's documentation and confirmed by testing in your own environment.