If you are planning to hike the Narrows from the bottom up—starting at Temple of Sinewava, you do not need to obtain a permit. However, if you are hiking from the top down, either as a day hike or an overnight trip, you will need a permit.
If you are planning to hike the Narrows in one day, but there are no advanced reservations left, don’t stress! Zion National Park will open the Last Minute Drawing 7 to 2 days before your rip date. If there are still spaces open after the Last Minute Drawing, they will become available for walk-in, to be obtained the day before your trip.
Backpacking in the Narrows requires backcountry campsite permit. There are 12 campsites in the gorge of the Narrows. Six of the twelve spots are available for advanced reservation, and the other half are only available as a walk-in permit—you can get these permits from 10 am to 5 pm on the day before your trip.