Vivo is expected to unveil its X300 series in October 2025, but the X300 Ultra could arrive much later in 2026. While it's pretty much confirmed that the X300 Ultra's main selling point will be its cameras, a new leak further elaborates on what could be the "X" factor that could truly differentiate it from others.
According to leaker Digital Chat Station, the Vivo X300 Ultra could boast a triple-rear camera setup consisting of a 200 MP wide main sensor and a 200 MP periscope lens. The third sensor is expected to be a 50 MP ultrawide camera.

The primary shooter is expected to be a Sony IMX09E, and as per Smart Pikachu on Weibo, the ultrawide could be the older LYT828, also known as IMX09A. The phone's periscope capabilities could be fueled by a Samsung HPB sensor.
Another post from DCS further elaborates on the camera's capabilities, like support for 2x and 4x lossless zoom in the main snapper. Besides, it could be a larger 1/1.12-inch sensor and boast better dynamic range.
The autofocus might also be greatly improved with the 16-channel 2x2 OCL system and the Zeiss partnership. As for selfies, the phone could boast a rather capable 50 MP unit.

Finally, unlike the expected MediaTek Dimensity 9500 in the Vivo X300 series, the Vivo X300 Ultra could boast the Snapdragon 8 Elite Gen 5. Both the SoCs are rumoured to breach 4 million points on AnTuTu.
Besides cameras, not much is known about the X300 Ultra. We also don't have its official launch date yet. Considering the X200 Ultra launched in April 2024, the X300 Ultra should arrive at around the same time. Stay tuned as we will cover future leaks and rumours about the device as it inches closer to launch.