How to Add a Signature in Outlook

Signatures don't sync everywhere

Depending on your account, signatures created in one version of Outlook may not appear in another, such as the mobile app. If a signature is missing, set it up in each app you use.

Signing a document attached to an email

An Outlook email signature is not the same as signing a contract. To sign an attached PDF, save it, sign it, and attach the signed copy to your reply.

If you would rather not install anything, eSignSimple's free Sign PDF tool is included with a free account (sign up with Google) and runs in your browser. You upload the PDF (it is encrypted at rest), draw or type a signature, add the date, and download the signed copy with an audit trail; it counts as one of your monthly documents.

Troubleshooting Outlook signatures

If your signature image shows as an attachment or a broken picture, the recipient's mail app may be blocking images; keep the signature mostly text. If new Outlook ignores the signature you set in classic Outlook, recreate it in new Outlook's Settings; the two versions do not always share signatures. If replies do not get a signature, check the default for replies and forwards in the same settings page.

Email signature vs. signing a document

An email signature is a sign-off. Signing a contract means showing intent to agree to a specific document, with evidence of who did it. To sign an attached PDF, follow how to sign a PDF; to sign without printing anything, see how to sign a PDF without printing. If you want a handwritten-style image for either use, how to create an electronic signature walks through the options.

What should a professional email signature include?

Your name, role and company, one phone number, and a website link cover almost everyone. Add pronouns or office hours if they help your recipients. Skip inspirational quotes, multiple social icons and large images; many mail apps block images by default, so a text-only signature is the most reliable. If you use Gmail as well, the matching steps are in how to sign a document in Gmail, which also covers replying with a signed attachment.

If a colleague sends you a Word attachment to sign, how to electronically sign a Word document covers the options without leaving Office.

How do I add a handwritten signature image to Outlook?

Create the image first: sign on white paper and photograph it, or draw or type it in our signature generator and download a PNG with a transparent background. Keep it small; around 300 to 400 pixels wide is enough for an email, and a file under 50 KB will not bloat every message you send.

In the signature editor, use the image button to insert the file, then resize it to roughly the height of two lines of text. Put your typed name and details under the image, not only in it: many recipients see images blocked until they click to load them, and screen readers cannot read text in a picture. Send yourself a test message, and open it on your phone as well as on a computer.

How do I use different signatures for new emails and replies?

A full signature on the first email to a client is useful; the same block repeated on every reply in a twenty-message thread is noise. Outlook lets you pick one default signature for new messages and another for replies and forwards. Create two signatures, for example "Full" with name, role, company, phone and website, and "Short" with just your name and role, then set each as the default for the matching case.

If you manage more than one mailbox, such as your own and a shared sales inbox, set the defaults per account in the same settings page. You can also switch signatures while writing a message, using the signature button in the message toolbar, when a particular email needs the longer version.

Why does my Outlook signature look different to the recipient?

Fonts are the usual culprit. If you pick a font the recipient's computer does not have, their mail app substitutes another, and line breaks and spacing change. Stick to widely available fonts such as Arial, Calibri, Verdana or Georgia. Tables used for layout can collapse on phones, so a simple stacked layout travels better.

Colours and dark mode cause the rest. A signature with black text on a white box can look like a glowing rectangle in a dark-mode inbox, and a logo with a white background behaves the same way. Use transparent PNGs and avoid background colours. If your signature includes legal disclaimers, keep them as short plain text; a long disclaimer in a tiny grey font is rarely read and often renders badly.

Signing a contract that arrives in Outlook

When a client emails you a contract in Outlook, the email signature plays no part in signing it. Save the attachment, sign it with your PDF app or a browser tool, and reply with the signed copy attached. In new Outlook and Outlook on the web, attachments can be downloaded from the attachment menu; on Windows, check your Downloads folder for the saved file.

If you are the one sending contracts from Outlook, consider replacing the attachment with a signing link. You write the usual cover email, then send the document through eSignSimple, and the client signs in the browser without downloading anything. You can track who has opened and signed it, and on paid plans automatic reminders follow up for you. The offer letter template and NDA template are typical documents teams send this way.

Our take

Sources and further reading

• Create and add an email signature in Outlook – Microsoft Support
• Insert a signature in a Word document – Microsoft Support