Disable third-party cookies in Firefox to stop some types of tracking by advertisers

Third-party cookies are cookies that are set by a website other than the one you are currently on. For example, cnn.com might have a Facebook like button on their site. That like button will set a cookie that can be read by Facebook. That would be considered a third-party cookie.

Some advertisers use these types of cookies to track your visits to the various websites on which they advertise. If you are concerned about this, you can disable third-party cookies in Firefox.

Note:
  • If you are concerned about tracking by advertisers, see also How do I turn on the Do Not Track feature?.
  • Disabling third-party cookies in Firefox can stop some types of tracking by advertisers, but not all.
  • Some websites (for instance, Microsoft's Hotmail, MSN, and Windows Live Mail webmail) use third-party cookies for purposes that are not necessarily privacy concerns, and disabling third-party cookies may cause problems with those sites.

Third-party cookie settings are available in the OptionsPreferences page's Privacy panelPrivacy & Security panel:

  1. Click the menu button New Fx Menu Fx57Menu and choose Options.Preferences.

  2. Select the PrivacyPrivacy & Security panel and go to the History section.

  3. In the drop-down menu next to Firefox will:Firefox will, choose Use custom settings for history.
    customhistory38 Fx56Privacy&Security-CustomHistory-new CustomHistory fx57 Fx60HistorySettings-UseCustom
  4. In the drop-down menu next to Accept third-party cookies choose Never.
    Privacy - Accept third-party cookies - Never 38 Fx56Privacy&Security-CustomHistory-never Fx57CustomHistory3rdPartyCookies-never
    Note: If after browsing with this setting, you realize you can't view properly some of your favorite websites, an intermediate solution is to set it to From visited. That will allow third-party cookies coming from previously visited websites.
  5. Close the about:preferences page. Any changes you've made will automatically be saved.
  1. Click the menu button New Fx Menu Fx57Menu and choose Options.Preferences.
  2. Select the Privacy & Security panel and go to the Cookies and Site Data section.
    Fx60CookiesAndSiteDataThird-partyNever
  3. In the drop-down menu next to Accept third-party cookies and site data choose Never.
    Note: If after browsing with this setting, you realize you can't view properly some of your favorite websites, an intermediate solution is to set it to From visited. That will allow third-party cookies coming from previously visited websites.
  4. Close the about:preferences page. Any changes you've made will automatically be saved.
  1. Click the menu button New Fx Menu Fx57Menu and choose Options.Preferences.
  2. Select the Privacy & Security panel and go to the Cookies and Site Data section.
    Fx63settings-AcceptCookies
  3. Choose Block cookies and site data and then use the drop-down menu next to Type blocked to choose the type of cookies to block. The options are listed in order from least restrictive to most restrictive. Some sites will not work properly with all cookies blocked.
    Fx63settings-BlockCookies
    Note: If you choose the more restrictive setting All third-party cookies (may cause websites to break) and you realize after browsing that you can't view properly some of your favorite websites, an intermediate solution is to set Firefox to block Cookies from unvisited websites. That will allow third-party cookies coming from previously visited websites. If you continue having problems, try the Third-party trackers (recommended) setting.
  4. Close the about:preferences page. Any changes you've made will automatically be saved.
// These fine people helped write this article:AliceWyman, Chris Ilias, jscher2000, novica, Tonnes, Michele Rodaro, Michael Verdi, scoobidiver, Swarnava Sengupta, ideato, Joni. You can help too - find out how.

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