How do you sign a document sent by email?
Updated
Short answer
If the email contains a signing link, click it and follow the steps; you don't need an account. If you received a plain attachment, open it in a PDF reader or an e-signature tool, add your signature, save it and send it back. Need the other party to sign too? Upload the document to an e-signature platform and send it for signature instead of emailing PDFs back and forth.
Option 1: the email contains a signing link
Many companies send documents through an e-signature service. The email then has a button such as "Review and sign". Click it, read the document, fill in the fields and sign by typing, drawing or choosing a signature. You usually don't need an account or an app, and afterwards you usually receive the signed copy, or a link to it, by email.
Only click links in emails you expected, and check that the link goes to the platform's own domain. Signing requests are a popular disguise for phishing.
Option 2: you received a PDF or Word attachment
Save the attachment first, then sign it with a tool you already have:
- PDF on a computer: open it in Adobe Acrobat Reader, or Preview on a Mac, and use the fill and sign tool to place your signature.
- Word document: export it to PDF first (File, then Save As or Export, then PDF) and sign the PDF. Word's own Signature Line needs a digital certificate before you can actually sign with it.
- On a phone: open the attachment from your mail app. Markup on iPhone and most PDF apps on Android let you draw a signature with your finger.
- Send it back: save the signed file under a new name and reply to the email with the signed version attached.
Why a pasted signature image is weak proof
Placing an image of your signature in a PDF is quick, but it proves little. Anyone can copy the image onto another document, and there is no record of who placed it, when, or whether the text changed afterwards.
For documents that matter, such as contracts, employment agreements or large quotes, it is better when the sender uses an e-signature platform that records that evidence in an audit trail. Read are electronic signatures legally binding.
Need someone else to sign? Skip the email ping-pong
If you are the one sending the document, don't attach a PDF and wait for a scan to come back. Send it for signature instead:
- Upload the PDF to an e-signature platform such as BuiltSign. Have a Word file? Save it as PDF first.
- Place a signature field for each signer. BuiltSign suggests fields itself when the PDF has labels such as "Signature" or "Date" next to a line; you confirm them.
- Enter the signers' email addresses. Each signer receives a personal signing link by email, and on paid plans optionally by SMS as well.
- Everyone signs in the browser, on a phone or laptop, without an account. When all have signed, everyone gets an email with a link to download the signed PDF, and you can download the audit certificate with the times, verification and document hashes.
Frequently asked questions
- Usually, yes. Most countries accept electronic signatures for ordinary contracts. What matters is that you can show who signed and that the document didn't change, which is easier with a signing platform than with a pasted image.
- Yes. Adobe Acrobat Reader, Preview on a Mac and Markup on iPhone let you add your signature for free. Sending documents to others for signature with an audit trail usually needs an e-signature service; BuiltSign has a 7-day free trial without a credit card.
- Save the signed file, reply to the original email, attach the signed file and send it. Check that you attached the signed version and not the original.