Last admission one hour before closing.
From 2 January to 30 AprilOpen every day 9.30-18.00
From 2 May to 31 AugustOpen every day 9.00-19.00
From 1st September to 31 DecemberOpen every day 9.30-18.00
January 1st, May 1st and December 25.
During periods of high tides, access to Mont-Saint-Michel, and therefore to the abbey, will be closed, only during 1h00 in the morning and the evening, at these periods: February 11th and 12th, March 10th to 13th, April 8th to 11th, May 7th and 8th, August 21th, September 17th to 20th, October 16th to 19th, November 15th to 17th, 2020.
It is your responsibility to check this, before organizing your visit to Mont-Saint-Michel. The abbey will not warn you about that.
Information about tides: https://www.ot-montsaintmichel.com/fr/horaire-marees/mont-saint-michel.htm