How to sign a PDF document with digital signature on Mac

Signing a PDF document with a digital signature on Mac is possible and is a fairly simple procedure, although unlike what happens to put a signature on a document with Preview , it is necessary to resort to third-party software to do it as you want. I will explain in the next few lines.

This procedure serves both to sign documents with government certificates as well as to do it with certificates issued by private companies. The process is exactly the same and all you have to do is choose the correct certificate when including the signature in the PDF.

Sign a PDF document on Mac with a digital certificate from the FNMT or similar

In order to do this, the first thing you will have to do is install the digital certificate on the computer. In the case of Mac, it is a very simple process, you will simply have to double click on the file that contains the certificate, enter your password if it is protected and finally enter the Mac administrator password to complete the install it in the macOS Keychain.

The next previous step to be able to sign PDF documents on Mac with digital signature is to download and install the software that allows you to do this. The most popular application for this purpose is Adobe Acrobat Reader DC, which you can download for free from its official website . On the web you will also see a Pro version of the software that offers more possibilities, although the free version is more than enough to sign documents .

Once the application has been downloaded and installed on the Mac and with the digital certificate in the macOS Keychain, everything is ready so that you can digitally sign any PDF document by following these steps:

  1. Open the Adobe Acrobat Reader DC application that you just installed.
  2. Click on the Tools tab at the top right of the screen and once inside select the Certificates tool that is identified with a green pen icon.
  3. Select the PDF file you want to sign and click on the Open button.
  4. Click on Digitally sign and select within the document the place where you want the signature to appear.
  5. Once you have selected the place where you want to place the signature, a new window will open in which you must select the digital certificate you want to use. Once selected, click on Continue.
  6. In the next window you will see a preview of what the signature will look like. In case you are satisfied, click on Sign and choose the name and location where you want to save the already signed document. Finally click on Save.

Once you have done these steps you will have a new digitally signed PDF file in the location you selected in the last step.

As you can see, it is a fairly simple process and it will not take you more than a few seconds once you have the application installed on your Mac. Taking into account that the presentation of documents digitally is increasingly common and that administrations Public are increasingly asking for documents to be submitted through digital means, this may be something that you have to resort to on more than one occasion. The Mac alliance, FNMT digital certificate and Acrobat Reader DC can save you from making more than one queue that can last hours in the shift register.