To sign a contract electronically, you either click the signing link the sender emailed you and complete the fields in your browser, or you open the PDF on your own device, add your signature with a built-in tool, and email it back. Federal law treats an electronic signature as legally equivalent to a handwritten one for most contracts, so a typed name, a finger-drawn signature, or a click on an “I Agree” button all bind you to the agreement when you intend them to.1Office of the Law Revision Counsel. 15 USC 7001 – General Rule of Validity2Office of the Law Revision Counsel. 15 USC Chapter 96 – Electronic Signatures in Global and National Commerce – Section: Definitions
Signing Through a Cloud Platform Link
Most contracts today arrive as an email from a service like DocuSign or Adobe Sign. This is the smoothest path because the platform handles delivery, identity checks, and record-keeping for you.
Click the link in the email. The document opens in your browser with signature fields, date fields, and any other required entries highlighted in colored boxes or marked with arrows. Work through the fields in order. When you reach a signature box, the platform gives you three ways to create your signature: type your name and let the system render it in a script-style font, draw it with your mouse or finger, or upload an image of your handwritten signature. Whichever method you pick, the platform saves it for the rest of the document so you only build it once.
Fill every required field. The submit button stays inactive until you do, which is a useful guardrail against skipping something. When everything is complete, the button labeled “Finish,” “Sign,” or “Submit” activates. Clicking it registers your intent to be bound.
The platform then locks the document so no one can alter the text or signatures afterward, shows you a confirmation screen with a download option, and routes the signed file to the sender and any other parties. Download your copy right then. You will also get an email with the fully executed version once every party has signed.
If the Sender Asks for Extra Identity Verification
Some senders bolt on an identity check before you can sign. Common ones are a one-time code sent by text message, knowledge-based questions drawn from public records like past addresses, or a photo of a government-issued ID. Complete these as prompted. They are not required for every transaction, but they strengthen the proof of who signed if the contract is ever challenged.
Signing a PDF Someone Emailed You
If the sender skipped the cloud platform and just attached a PDF, you sign it on your own device and email it back. The tools differ by operating system.
On a Mac
Every Mac includes Preview, which has a signature tool built in. Right-click the PDF, open it with Preview, click the Markup icon (the pen-tip symbol in the toolbar), and select the signature button. You can create a signature by drawing it on your trackpad with your finger, or by writing your name on a piece of paper and holding it up to your Mac’s camera. Click Done when you are satisfied. The signature saves for future use.
To place it, click the signature button again, pick your saved signature, and drag it onto the signing line. Resize it by pulling the corners. Save the file, then attach the signed version to a reply email. Double-check that you are sending the signed PDF and not the original blank one.
On Windows
Windows does not include a built-in PDF signing tool. The free version of Adobe Acrobat Reader has a Fill and Sign feature that does the same job: open the PDF, select Fill and Sign from the tools menu, click the signature field, and choose to type, draw, or upload an image of your signature. Save the file locally and reply with it attached.
If you would rather not install anything, several vendors offer free browser-based PDF signers where you upload the file, add your signature, and download the result. Any modern browser works, on Windows, macOS, or Linux.
On iPhone or iPad
Apple’s Markup tool is built into iOS and works inside Mail, Files, and Notes. Open the PDF attachment, tap the Markup button, tap the plus icon, and choose “Add Signature.” Sign with your finger on the screen. Tap Done, then drag and resize the signature to fit the signing line.3Apple. Fill Out Forms, Sign Documents, and Create Signatures on iPhone Saved signatures carry between apps, so a second signing goes faster. Tap Done again and use the share menu to email the signed file back or save it to Files.
On Android
Android does not ship with a universal PDF signing tool the way iOS does. Google Drive and Google Docs handle basic annotations, but the more reliable free option is to install Adobe Acrobat Reader from the Play Store, open the PDF, select Fill and Sign, and draw your signature on the screen. Save and share through the share menu. Browser-based signers work on Android too.
One weakness of signing locally on any device: you do not get the automatic tamper-proof audit trail a cloud platform produces. Keeping your own email records matters more when you take this route.
What to Have Ready Before You Start
Whatever device or platform you use, three things need to be within reach:
- A verified email address. The sender delivers the document or link here, and your address becomes part of the audit trail that proves who signed.
- Your full legal name. The platform ties your name to the digital record. Some systems also ask for your job title, company name, or mailing address.
- Access to the document itself. That means either the signing link or an app that can open and annotate the attached PDF.
Contracts You Cannot Sign Electronically
The ESIGN Act carves out categories where an electronic signature does not satisfy the legal requirement, so an e-signed version may not hold up.4Office of the Law Revision Counsel. 15 USC 7003 – Specific Exceptions The main ones:
- Wills, codicils, and testamentary trusts. State execution rules almost universally require handwritten signatures and witnesses.
- Documents governed by state adoption, divorce, and other family law statutes.
- Most Uniform Commercial Code transactions, including negotiable instruments under UCC Article 3 and secured transactions under Article 9. UCC Articles 2 and 2A, covering sales and leases of goods, are included in ESIGN.
- Court orders, official notices, and pleadings, which follow court-specific filing rules.
- Cancellation notices for utilities, health insurance, and life insurance; default and foreclosure notices on a primary residence; and product recall notices.
- Shipping and handling documents for hazardous materials, pesticides, and toxic substances.
States can add their own exclusions. If you are signing something unusual like a deed or a power of attorney, check your state’s electronic transactions law before assuming an e-signature will hold up.
Save Proof That You Signed
Cloud signing platforms generate an audit trail or certificate of completion that records the signer’s name and email, a timestamp for each action, the IP address of the device used, and the authentication method. That log is what gives the signature its evidentiary weight in a dispute. The platform also locks the finished document cryptographically, so later tampering breaks the seal and shows up immediately. Download the audit trail along with the signed contract.
If you signed locally rather than through a cloud platform, your proof comes from your copy of the signed file, the email you sent it with, and any confirming reply from the other party. Keep all of them.
Store your copy somewhere secure and backed up. An encrypted cloud folder or a dedicated contracts directory on a backed-up drive both work. For tax-related contracts, the IRS expects supporting records for at least three years after filing the relevant return, and up to six or seven years in certain situations. For general business contracts, keep the signed document for the length of the contract plus the longest statute of limitations that could apply to a dispute, which in most states runs four to six years for written contracts. Deleting a signed contract before the relationship and all potential claims are resolved is easy to do and impossible to undo.