Based on years of experience testing VPNs for all sorts of use-cases, these are the factors I consider to be the most important when choosing a VPN for Amazon Prime Video.
Ability to unblock Amazon Prime content
Not every VPN can give you access to Amazon Prime Video content. If you want to use a VPN for Prime Video, then the first thing you’ll want to determine is whether the VPN you’re considering can unblock Prime Video content. In my testing, Surfshark and Proton VPN were the best at accessing content from multiple regions, and ExpressVPN and NordVPN were capable of accessing US-based content. Most VPNs offer some sort of money-back guarantee, so you can try a few out to see which one works best for you.
Speed
Many VPNs may cut your base internet speeds by 50% or more, which can make for a rough streaming experience filled with buffering,
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