How to Sign a Contract Online for Free (No Printing)

Someone sends you a contract PDF and asks you to "sign and send it back." The old way — print it, sign with a pen, scan it, email the blurry scan — is slow and needs hardware you may not have. You can add a legally valid signature to the PDF in your browser in under a minute. Here's how, plus a straight explanation of when a free signed PDF is enough and when you need a full e-signature service.

Sign it in your browser with Sign PDF

The fastest route, works on any device.

For a longer walkthrough with tips on making a clean signature image, see how to add a signature to a PDF.

Free built-in alternatives

If you'd rather not upload the file anywhere, both major desktop platforms can sign a PDF locally:

macOS Preview

1. Open the PDF in Preview.
2. Click the Markup toolbar icon, then the Signature button.
3. Create a signature via trackpad, or hold a signed piece of paper up to your camera — Preview captures it.
4. Click to drop the signature onto the signature line, resize, and File → Export as PDF.

Preview stores your signature for reuse, so the second contract takes ten seconds. Everything happens on your Mac — nothing is uploaded.

Adobe Acrobat Reader — Fill & Sign (Windows, free)

The free Reader (not paid Acrobat Pro) includes Fill & Sign:

1. Open the PDF in Acrobat Reader.
2. Click Fill & Sign in the right-hand tools panel.
3. Click Sign, then add your signature by typing, drawing, or uploading an image.
4. Place it, then File → Save.

This is free and built into the Reader most Windows machines already have. It also lets you type into any flat form fields on the contract.

Are electronic signatures legally valid?

For the vast majority of everyday agreements, yes — and this is the part people most often get wrong out of caution. This is general information, not legal advice.

• United States (ESIGN Act, 2000 + UETA): electronic signatures are legally valid and enforceable for most contracts. The law cares about intent to sign and consent to do business electronically — not whether you used a fancy platform. A typed or drawn signature on a PDF, applied deliberately, generally qualifies.
• European Union (eIDAS): recognizes electronic signatures across three tiers — Simple (SES), Advanced (AES), and Qualified (QES). A signature drawn or typed onto a PDF is a Simple electronic signature, valid and admissible for ordinary contracts. Higher tiers add identity verification and are required only for specific regulated cases.

What still commonly requires a handwritten (wet) signature or a notary: wills and testamentary trusts, some real-estate deeds, certain family-law documents, and a handful of court filings. When significant money or legal consequence is on the line, confirm the requirement for your jurisdiction.

Simple signed PDF vs. a full e-sign service

Both produce a signed document; they differ in the evidence trail behind the signature.

The honest summary: a signature drawn onto a PDF is legally valid, but it carries no built-in record of who applied it. A full e-sign service adds that verifiable audit trail — email verification, timestamps, IP logging, a signing certificate. If the contract is routine and trusted, you don't need that overhead. If it's high-stakes or could end up in a dispute, the audit trail is worth it.

A note on security

A contract often contains personal or financial details. Whichever method you use, don't leave the signed file sitting in shared cloud folders. If you need to lock it, add a password with Protect PDF before sending, and share the password separately. pdfty deletes uploaded files within 1 hour and never watermarks them.

Frequently asked questions

Is signing a contract with an online tool legally binding?

For most everyday contracts, yes. Under the U.S. ESIGN Act and EU eIDAS, an electronic signature applied with intent is valid and enforceable. A few document types (wills, some deeds, certain court filings) still require a wet signature or notary — check your jurisdiction for those.

Do I need to print and scan the contract?

No. That's the whole point of signing digitally. Add your signature directly to the PDF with Sign PDF, macOS Preview, or Acrobat Reader's Fill & Sign, then send the file back.

What's the difference between this and DocuSign-style services?

A free signed PDF is a valid signature but has no built-in audit trail. Dedicated e-sign services add verification of who signed, timestamps, and a tamper-evident certificate. Use the free method for routine agreements; use a full service for high-stakes or multi-party contracts.

How do I create my signature if I don't have a scanner?

Draw it with your mouse or finger directly in Sign PDF, type your name in a signature font, or hold a paper signature up to your webcam (Preview and Acrobat Reader both support camera capture).

Can I add the date and my initials too?

Yes. In Sign PDF you can place a typed date and initials the same way you place the signature. Acrobat Reader's Fill & Sign and Preview's Markup both let you add text and initials as well.

Is it safe to upload a contract to sign it?

pdfty processes the file, lets you download the signed version, and deletes it from the server within 1 hour — no sign-up, no watermark. If you'd rather keep everything offline, use macOS Preview or Acrobat Reader, which sign locally on your machine.

Can the other person tell I signed electronically?

Yes — the signature appears on the page just like a scanned one, and it's clearly an electronic signature. That's expected and accepted for electronic contracts. If they specifically require a wet signature or notarization, they'll say so.