Currently, it is 30 dollars per vehicle to enter the Grand Canyon. Different prices if entering by foot or tour group. I would agree with previous post about getting the yearly pass, which currently costs 80 dollars. It gets you into all National Parks that charge per vehicle.
If you plan on visiting more than once or seeing other national parks then it is worth buying the National Park Pass for the year. Can be bought at the GC main entrance as you would when you pay the day entry.
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