Cookies are enabled by default in Firefox, but you can change what Firefox does with them
Firefox accepts cookies automatically when you visit most websites. You do not need to turn anything on. If you have disabled cookies and want to turn them back on, or if you want to change how Firefox handles cookies from specific websites, the settings are in one place in Firefox's preferences.
The steps below work on Firefox for Windows, Mac, and Linux. The menu names and locations are the same across all three.
Key Takeaways
- Cookies are turned on in Firefox by default, so most websites will set them without any action from you.
- To turn cookies back on after disabling them, open Firefox preferences, go to Privacy & Security, and change the Cookies setting under History.
- You can allow cookies from all websites, block them entirely, or block only third-party cookies that track you across sites.
- If a single website is not working, you can add it to an exception list so Firefox accepts its cookies while blocking cookies elsewhere.
How to check your current cookie settings
Open Firefox and click the menu button (three horizontal lines) in the top right corner. Select Settings. On the left side, click Privacy & Security.
Scroll down to the section labeled Cookies and Site Data. You will see a dropdown menu that shows your current setting. The default is Allow all cookies, which means Firefox accepts cookies from every website you visit.
How to turn cookies back on if you disabled them
If you previously turned off cookies and now want to enable them again, follow the steps above to reach the Cookies and Site Data section. Click the dropdown menu and select Allow all cookies. Firefox will immediately start accepting cookies from websites.
If you want more control, you can choose Allow cookies and site data by default instead. This option blocks cookies from third-party trackers (companies that follow you across multiple websites) while still allowing the website you are visiting to set cookies. This is a middle ground between full cookie acceptance and blocking all cookies.
The three main cookie settings explained
Allow all cookies means Firefox stores cookies from every website. This is the default. Websites load faster because they can remember your login, shopping cart, and preferences. The trade-off is that some companies can track your activity across different websites.
Allow cookies and site data by default blocks third-party cookies — the ones set by advertisers and analytics companies — while allowing the website itself to set cookies. Most websites still work normally, and you get some tracking protection without breaking functionality.
Reject all cookies blocks every cookie. Many websites will not work properly. You may see repeated login screens, shopping carts that do not remember items, or broken page layouts. Choose this only if you have a specific reason to block all cookies.
How to allow cookies from one website while blocking others
If you have blocked all cookies but one website is not working, you can add an exception. Go to Settings > Privacy & Security and scroll to Cookies and Site Data. Under the dropdown menu, click Manage Exceptions.
Type the website address (for example, example.com) into the text box and click Allow. Firefox will now accept cookies from that website only. When you visit other websites, Firefox will still block their cookies according to your main setting.
To remove an exception later, go back to Manage Exceptions, find the website in the list, and click the X button next to it.
What to do if a website says cookies are disabled
If a website tells you that cookies are disabled and you need to turn them on, first check your Firefox cookie setting using the steps above. If it is already set to allow cookies, the problem is usually something else.
Clear your browser cache and cookies for that specific website. Go to Settings > Privacy & Security, scroll to Cookies and Site Data, and click Manage Data. Search for the website name, select it, and click Remove Selected. Then reload the website and try again.
If the website still does not work, it may require a type of cookie that Firefox's privacy settings are blocking. Try changing your main cookie setting to Allow all cookies temporarily, reload the website, and see if it works. If it does, you can add that website to your exceptions list instead of leaving all cookies enabled.
How cookies affect your browsing speed and privacy
Cookies make websites faster because they store information locally on your computer instead of making the website fetch it every time. When you log into an email account, a cookie remembers you are logged in. When you add items to a shopping cart, a cookie keeps track of them. Without cookies, you would have to log in again every time you visit.
The privacy trade-off is that some cookies track you across websites. An advertiser might set a cookie on one website, then recognize you on another website you visit later. Blocking third-party cookies stops this kind of tracking without breaking most websites.
Frequently Asked Questions
Do I need to restart Firefox after changing cookie settings?
No. Firefox applies cookie setting changes immediately. You do not need to close and reopen the browser. If a website is still not working after you change the setting, try clearing that website's data and reloading the page.
What is the difference between cookies and site data?
Cookies are small text files that store login information and preferences. Site data includes cookies plus other information websites store, like cached images and offline data. Firefox treats them together in the same settings menu, so enabling or disabling one affects both.
Can I allow cookies from one website but block them from another?
Yes. Set your main cookie setting to Reject all cookies, then use Manage Exceptions to add the websites where you want cookies allowed. Firefox will block cookies everywhere except the sites you list.
Will turning on cookies slow down Firefox?
No. Cookies are small files and do not slow down your browser. In fact, allowing cookies usually makes websites load faster because the site does not have to fetch your information from its server every time you visit.
What happens if I clear cookies?
You will be logged out of most websites, and websites will forget your preferences and shopping cart contents. You will have to log in again the next time you visit. Clearing cookies does not change your cookie settings — Firefox will still accept new cookies from websites you visit.