Electronic contracts are only legally valid when signed with a valid digital signature. Foxit Reader is the most popular free tool for this: directly signing PDF files using a digital certificate stored on a USB token, eliminating the need for printing or paid software. This article provides detailed instructions on how to perform electronic digital signing with specific step-by-step illustrations.
Three things to prepare
Foxit Reader 9.5.0+
Versions lower than 9.5.0 do not have digital signature functionality. If your computer is running an older version, please update it before proceeding.
The USB Token is still valid.
Insert the token into the machine and install the token manager from the digital certificate provider. The installation window will automatically appear if it is not already installed.
PDF file needs to be signed.
The completed contract, appendix, or declaration should be exported in PDF format.
⚠️ Runs only on Windows
Foxit Reader on macOS and Linux does not currently support digital signing using USB tokens. If you are using a Mac, you will need to switch to a Windows machine.
Open the contract file using Foxit Reader.
Launch Foxit Reader and open the PDF file you need to sign. Double-check the content, contract number, and date one last time — after digital signing, any edits will invalidate the signature.
Select the Place Signature feature.
- Switch to card 'Protect' On the ribbon, click 'Sign & Certify' then select 'Place Signature…' in the dropdown list.
- The mouse cursor changes to a plus sign. Hold down the left mouse button and drag a rectangular frame over the box designated for your signature. The size of this frame will determine the final size of the displayed signature stamp.
Declare signature information
The Sign Document dialog box appears with information read from the USB Token. If the signature information is not available, select 'Refresh ID List'.
Check the following three items and then click. 'Sign':
- Sign As — Choose the correct digital certificate you need. If the machine has multiple tokens plugged in or multiple expired certificates, this is the easiest place to make a mistake.
- Appearance Type — A sample display of the signature stamp on a document.
- Reason and Location — Reason for signing and location; not mandatory but recommended for future verification purposes.
Name the file and save the signed version.
Foxit requires you to save the file as a new one before signing. It's recommended to name it with a clear suffix to distinguish it from the original, choose a save location, and then click. 'Save'.
Enter the PIN code of the USB Token
The token management software requires authentication. Enter your PIN and then click. 'Log in'Entering the wrong code multiple times in a row may lock your token — if you don't remember it, contact your digital certificate provider to have it reissued instead of trying again.
If you enter the correct PIN for the USB Token, the software will digitally sign the document. Your digital signature will appear in the selected location, and the digital signing process is complete.
Verify the signature after signing.
To check, click the pen icon in the vertical toolbar on the left — the Digital Signatures panel lists the signer, the time of signing, and the validity status of the signature.
Four things to remember
- Check the expiration date of the digital certificate. Signatures created on expired certificates are invalid. Keep track of the expiration date and renew at least 15 days in advance.
- Signing it means the content is finalized. Any subsequent changes—including adding a space—will render the signature invalid. Double-check before signing.
- In the correct order of the parties. For multi-party contracts, each party signs sequentially on the same file; each subsequent party signs on a copy already signed by the previous party, without creating a new file in parallel.
- Keep the original copy. Keep both unsigned and signed files in the same folder, naming them according to a consistent convention for comparison and auditing purposes.
💡 Can't use Foxit Reader?
Adobe Acrobat Reader DC or the dedicated digital signature software of a certificate provider will produce equivalent results. The digital signatures created adhere to the same PAdES standard, so the signed file can be read and authenticated by either software.