To get 4k UHD on Amazon Prime Video you only need the Prime subscription. Thankfully, Amazon does not charge more for streaming 4k Ultra HD movies and shows like Netflix does. However, you will need sufficient internet bandwidth (at least 25Mbps recommended) and a 4k TV or 4k monitor. If you want to enjoy HDR, the TV must be HDR (Dolby Vision or HDR10) capable. Learn How To Get 4k/HDR On Amazon Prime.