Free unlimited storage for Pixel, Pixel 2, and Pixel 3 users
If you have a Pixel, you get unlimited free storage at Original quality for photos and videos taken and uploaded from your phone. You won’t be able to use “High quality.”
If you have the Pixel 2 or Pixel 3, you get unlimited free storage at Original quality for photos and videos taken and uploaded from your phone before your offer period ends.
Pixel 2 offer ends Jan 16, 2021.
Pixel 3 offer ends Jan 31, 2022.
https://support.google.com/photos/answer/6220791?co=GENIE.Platform%3DDesktop&hl=en