Cookies are small files that websites store on your computer to remember you
When you visit a website, it may ask Firefox to save a cookie — a tiny file that stores information like your login details, shopping cart contents, or your language preference. Without cookies enabled, many websites won't work correctly: you'll get logged out unexpectedly, your shopping cart will empty, or you'll see error messages. Firefox lets you control cookies completely, and turning them on takes about one minute.
Most people should enable cookies. The only reason to keep them off is if you're concerned about websites tracking your browsing habits across the internet — but even then, Firefox has a middle-ground option that blocks tracking while letting individual websites function normally.
Key Takeaways
- Firefox has cookies enabled by default, so you likely don't need to change anything unless you deliberately turned them off.
- If websites aren't working properly — you're getting logged out, items disappear from your cart, or pages show errors — cookies are usually the problem.
- You can turn cookies on in Firefox Settings under Privacy & Security in about one minute.
- Firefox offers three cookie settings: allow all cookies, block third-party tracking cookies, or block all cookies — most people should use the first or second option.
Check if cookies are already enabled in Firefox
Firefox turns cookies on by default, so your cookies may already be working. The fastest way to check is to try logging into a website you use regularly — Gmail, your bank, or any site where you have an account. If you can log in and stay logged in after closing and reopening Firefox, cookies are enabled.
If you get logged out immediately, or if a website tells you "cookies must be enabled," then you need to turn them on. Open Firefox and follow the steps below.
Turn on cookies in Firefox Settings
Step 1: Open Firefox and click the three horizontal lines (hamburger menu) in the top right corner of the window.
Step 2: Click Settings from the menu that appears.
Step 3: On the left side, click Privacy & Security.
Step 4: Scroll down to the section labeled Cookies and Site Data. You'll see a box with radio button options. The default setting is usually "Manage cookies and site data" or "Allow cookies and site data." If you see "Block all cookies," that's why websites aren't working — click the radio button next to "Manage cookies and site data" instead.
Step 5: Close the Settings tab. Cookies are now enabled, and websites should work normally the next time you visit them.
Understand Firefox's three cookie settings
Firefox gives you three main choices for how to handle cookies. The first option, "Manage cookies and site data," is the most common and allows websites to store cookies normally. This is what most people should use.
The second option, "Block cookies and site data from unvisited sites," keeps you logged in to websites you visit regularly but blocks third-party tracking cookies — files that follow you across different websites to build a profile of your browsing. This is a good middle ground if you want websites to work but don't want advertisers tracking you.
The third option, "Block all cookies and site data," turns off cookies completely. Websites won't remember you, you'll get logged out frequently, and shopping carts will empty. Only use this if you have a specific reason to block all cookies.
Clear old cookies if websites still aren't working
Sometimes old or corrupted cookies prevent a website from loading properly, even after you've turned cookies on. If a website still isn't working after you've enabled cookies, try clearing the cookies for that specific site.
Step 1: Go to the website that isn't working.
Step 2: Click the lock icon or information icon to the left of the web address at the top of the page.
Step 3: Click Clear Site Data or Manage Cookies (the exact wording varies by Firefox version).
Step 4: Check the box next to Cookies and click Clear. Refresh the page, and the website should work normally.
Allow cookies for specific websites only
If you want cookies enabled overall but blocked for certain websites you don't trust, Firefox lets you set rules for individual sites. Go to any website, click the lock icon next to the address bar, and look for a Cookies section. You can toggle cookies on or off for that site alone without affecting your global settings.
This is useful if a website is trying to set cookies you don't want, but you still want to use the site. You can allow the essential cookies that make the site work while blocking others.
Frequently Asked Questions
Will enabling cookies make my computer less secure?
Cookies themselves don't pose a security risk — they're just small text files. However, if you're on an unsecured public Wi-Fi network, someone could theoretically intercept cookies and use them to log into your accounts. Use a VPN on public Wi-Fi if you're concerned, but enabling cookies on your home network is safe.
What's the difference between cookies and tracking?
Cookies are files websites store on your computer. Tracking happens when advertisers use cookies to follow you across multiple websites and build a profile of your interests. Firefox's "Block cookies and site data from unvisited sites" option stops most tracking while keeping websites functional.
If I clear cookies, will I lose my passwords?
No. Firefox stores passwords separately from cookies in its password manager. Clearing cookies will log you out of websites, but your saved passwords remain. You can log back in immediately using your saved password.
Why does Firefox keep asking me about cookies?
Some websites show a cookie consent banner asking permission to store cookies. This is required by law in many countries. You can click "Accept" to allow cookies, and Firefox will remember your choice for that site.