Best VPN Extensions for Firefox: Top Add-ons, Privacy Checks and Prices

Proton VPN, Surfshark and PureVPN on the same fields

Each has a checkout catch: Proton roughly doubles its price on renewal after two years, Surfshark bills the trial automatically on day seven, and PureVPN refuses refunds on renewals.

Why Proton VPN leads a list that weights apps at 35%

Ecosystem, worth 35% of each score, covers having clients on every platform, the extension itself, split tunnelling, ad blocking and support quality. Privacy contributes 21.7% and security 14.4%. Surfshark and PureVPN max that column at 9.0, Proton has 7.1, but Proton recovers the gap on the privacy and security side: its apps are open source, it publishes a warrant canary and transparency reports, and it sits in Switzerland beyond any Eyes alliance. NordVPN lands fourth because a value mark of 3.1 drags down an overall score higher than the two runners-up.

Built-in Firefox VPN, Mozilla VPN or a provider add-on

The built-in feature routes traffic through a Fastly-run proxy and toggles per site from the toolbar. Mozilla VPN is a different product, a paid device-wide app on Mullvad servers, ranking 33rd: its Firefox add-on supports only Windows, and our data show no independent audit of its no-logs claim.

What a Firefox add-on hides and what it leaves exposed

An add-on steers only requests made by Firefox; mail clients and system updates exit from your home IP, so the desktop app matters for whole-device cover. We label 14 extensions here as proxies, among them NordVPN, Windscribe, CyberGhost, Hide.me and Urban VPN: the visible address changes, but how deeply the hop gets encrypted depends on the vendor. Two more entries are not tunnels in any real sense: Disconnect offers a tracker blocker, while Bright VPN's add-on merely serves as a remote control for the separate desktop program.

Installing from addons.mozilla.org and checking permissions

Follow the link from the provider's site, because copycat listings exist. A VPN add-on legitimately needs permission to manage the browser proxy and read website data everywhere; that same broad access is what makes a shady free one risky. The private-window switch is where people slip up: without permission there, those tabs bypass the tunnel entirely. Kill switch appears in 36 of the 54 services, split tunnelling in 33, and in-extension split tunnelling lets one site bypass the tunnel while others stay proxied.

Urban VPN and free add-ons with low scores

Urban VPN ranks 40th of 54 with a privacy score of zero. Its policy describes the parent as a data broker selling marketing insights drawn from browsing and lists visited URLs plus AI chatbot prompts among the collected items; in December 2025, the Urban VPN Proxy extension was reported harvesting users' AI chatbot conversations. Across the page, three providers admit storing the connection IP and another eight do so partly or temporarily; Urban VPN and LibertyShield have publicly reported incidents. The free extensions ranking compares the 25 services offering a free plan.

FAQ

Short answer

Pick Proton VPN if privacy comes first and you want a free tier, Surfshark when device limits annoy you, PureVPN where the entry price of €1.85 a month matters most. If all you need is a new IP in the browser, the built-in feature costs nothing and switches on per site.