How to Keep and Share Files Securely Online

Illustration of someone locking a cloud in the sky with a key.

While all personal and professional data should be handled securely, some of your files are particularly important to keep safe. These include any files that contain your date of birth, address, passport number, driver’s license number, social security number, bank account number, health records, income tax records, etc. Depending on your situation, some of your audio, image, and video files may also be confidential or sensitive.

In addition to securing such data on your devices, one of the best ways to protect it from falling into the wrong hands is to never store or share it online. Do not share confidential or sensitive files with anyone on the internet, unless you absolutely have to. While you have almost full control over your data’s security while it stays on your devices, you lose much of this control the moment you upload it online or share with anyone.

But when you have or choose to keep or share files online, it is important that you know how to do it in a safe and secure way.

Safely storing files online

From Dropbox to Google Drive to OneDrive to Tresorit and others, there are many popular file storage and cloud storage services to choose from. These services allow you to have easy access to your files on any device anywhere. They also allow you to give other people access to some of your files and collaborate with them on those files.

If you use file storage or cloud storage services, follow these steps to protect your data:

  • Use a reliable service and make sure that it encrypts your files in transit and when stored. When possible, choose zero-knowledge encrypted options such as Tresorit and to ensure that your data is secure even if your cloud provider is compromised.
  • Secure your accounts on such services with strong and unique passwords.
  • Enable two-factor authentication on your accounts to protect your file in case someone steals or cracks your passwords.
  • If you give other people access to your files online, make sure that they also secure their accounts with strong passwords and two-factor authentication.
  • Limit the amount of sensitive and confidential files you keep online. Do not upload important personal or professional files on more than one service, and remove these files when you no longer need them online.

Sharing files securely

If you need to send a sensitive or confidential file to someone, there are several easy ways to do it. Whichever way you go with, you need to understand the risks involved in sharing sensitive data using this method and know how to minimize these risks.

  • File-sharing services
    You can share files by uploading them to an online storage or file-sharing service and sending someone a link to these files. If you choose this method, make sure you use precautions listed above. You also need to treat the sharing links you generate as sensitive data.
  • Email
    You can also use email to send sensitive or confidential files. Follow these precautions to do so in a secure way:
    • Use a reliable and encrypted email service. ProtonMail and Tutanota offer free, open-source, end-to-end encrypted email service.
    • Secure your email account with a strong and unique password.
    • Enable two-factor authentication on your email account.
    • Make sure that the people to whom you send the files also have their accounts secured with a strong password and two-factor authentication.
    • As soon as you know that your files have been received, delete them from your email account. Remember also to delete these emails from the trash folder.
  • Messaging apps
    You can also use messaging apps to share the less confidential yet sensitive information. These apps are perfect for sharing images and videos of personal nature. If you do so, make sure that you use a reliable end-to-end encrypted messenger app such as Signal or Wire. You can use disappearing messages to make sure that your files do not stay on the app.