Best VPN Firefox Extensions in 2026: Setup and Real Picks

A VPN Firefox extension only encrypts what happens inside Firefox. Your torrent client, your email app, and every other program on your machine keep talking to the internet with no protection at all. That distinction decides whether an extension is the right tool for you or a false sense of security.

The good news: Firefox’s extension policy is stricter than Chrome’s, so the lineup here is smaller but more trustworthy. A few providers that refuse to touch the Chrome Web Store show up here instead.

Which VPNs actually have a Firefox extension

Per our comparison data, most major providers ship a real Firefox extension. ProtonVPN is the notable holdout: no browser add-on, desktop and mobile apps only.

The interesting reversal here is Mullvad. It refuses to ship a Chrome extension on principle, objecting to how Chrome’s Manifest V3 handles extension permissions, but it maintains a full Firefox extension because Firefox’s model doesn’t raise the same objections. If you care about that kind of stance, Firefox is where Mullvad actually shows up.

What a Firefox extension protects, and what it doesn’t

Does: hides your IP from every website you visit in Firefox, encrypts the traffic between Firefox and the provider’s server, unblocks geo-restricted content inside the browser, and switches server locations in a couple of clicks. It’s lighter than the full app, installs in seconds, and works on machines where you’re not allowed to install standalone software.

Doesn’t: touch anything outside Firefox. Other browsers on the same machine, your torrent client, background system traffic, and any app that isn’t Firefox stay exposed. Most extensions also skip the kill switch protections built into the desktop app, so a dropped connection can leak traffic instead of blocking it. For anything that needs to hide from your ISP at the system level, read our guide to what your ISP can actually see before assuming the extension has you covered.

Technically, most of these extensions are encrypted proxies rather than full VPN tunnels, similar to what we found when we tested VPN vs proxy setups directly. That’s enough for IP masking and browser-level geo-unblocking, not enough for anything system-wide.

When the extension is enough (and when it isn’t)

Use the extension alone when the job stays inside the browser: checking whether a geo-blocked page loads from another country, hiding your IP from a specific site, or switching locations quickly while comparing prices across regions. It’s also the practical choice on a locked-down work laptop where you can’t install anything else.

Reach for the full desktop app when the stakes go beyond the browser: torrenting, gaming, public Wi-Fi, or any situation where a dropped connection matters. The app brings the kill switch, system-wide DNS handling, and protocol choice that the extension doesn’t have.

Realistically, most people should run both. Every provider in the table above bundles the extension with the same subscription as the app, so there’s no reason to pick one over the other once you’re paying anyway.

Want to compare all VPNs side by side? Check our full VPN comparison table with scores across 18 criteria.

How to install a VPN extension in Firefox: step by step

1. Pick a provider from the table above. Don’t start from Mozilla’s add-on store search results; go to the provider’s own site first so you’re getting the official extension, not a lookalike.
2. Subscribe or confirm you already have an account. You need an active plan (or a free Windscribe account) before the extension does anything.
3. Open the Firefox Add-ons page for that provider, either from a link on their site or by searching the exact provider name in addons.mozilla.org.
4. Click “Add to Firefox” and approve the permissions prompt. A VPN extension will ask to read and modify data on all sites, which is expected since it has to route your traffic.
5. Pin the extension icon to your toolbar so you can see connection status at a glance.
6. Log in with your subscription credentials inside the extension popup.
7. Turn on WebRTC leak protection in the extension’s settings if it’s not on by default. This is the one browser hole that can expose your real IP even while the extension is “connected.”
8. Pick a server location and connect. Most extensions default to the fastest server; switch manually if you need a specific country.
9. Set per-site rules if the extension supports them, so sites like your bank skip the tunnel while streaming sites use it.

That’s the whole process for every provider in the table. The differences between them show up in the settings menu, not the install flow.

Red flags: the free “VPN” extensions to skip

Mozilla’s add-on store has its own crop of free VPN extensions with glowing ratings and no visible business model. Treat them the way security researchers do: as data collection wearing a privacy badge. A browser extension sits in the perfect spot to log every page you visit, and free proxy services running at scale need to fund that somehow.

Specific things to check before installing anything unfamiliar: does the provider publish an independent no-logs audit, does the extension come from a company with a real desktop app and a business model beyond the browser add-on, and does the permissions request match what a VPN needs (not more). If a free extension fails all three, skip it. Windscribe is the one legitimate free option in this list, with a transparent 10GB monthly cap and a paid tier funding the free one honestly.

Setup details worth getting right

WebRTC leak protection should be on by default in every extension listed above; confirm it rather than assume it. Auto-connect on untrusted networks is worth enabling if the extension supports it, since it removes the “I forgot to connect” gap. Ad and tracker blocking, where offered (NordVPN’s Threat Protection, Surfshark’s CleanWeb, Windscribe’s R.O.B.E.R.T.), is worth leaving on; it doesn’t cost speed and it strips junk before it loads.

One thing specific to Firefox: because Mozilla’s extension review process is stricter than Chrome’s, a Firefox VPN extension is somewhat less likely to be a disguised data broker than the equivalent on Chrome. That’s not a guarantee, just a real difference in how the two stores are policed.

Extension or app: the short version

Extension only, if you’re just checking a geo-blocked page or masking your IP for a quick browsing session. Full app, if you’re torrenting, gaming, on public Wi-Fi, or need protection for anything outside Firefox. Both, if you’re already paying for a subscription, since the extension comes free with it anyway.

For a deeper look at what a lightweight free option can and can’t do beyond the extension itself, our ProtonVPN review covers the desktop-only alternative, and our Windscribe review covers the honest free tier behind the extension in this table.