गूफ़

Margot says their future meet-up will happen in 2041, but when Daniel leaves her a postcard to remind her of this, he writes 2040 as the year of their meet-up.

In the beginning of the film a day passes by showing the relative movement of the sun - the light moving on the walls. The sun moves from west to east.

Margot makes a date for 2 PM Eastern Standard Time in August, when it must be Eastern Daylight Time.

The police car Geraldine gets into in the end does not have the usual barrier between the passenger and driver seats as is characteristic of police vehicles to protect the officers/driver from any potential hostile acts by prisoners.

Right at the beginning of the movie, Michelle Williams appears to be making muffins, she puts them into the (presumably hot) oven-but then leans against the oven door.

There is no magic chemical which you can add to pool-water for it to change color when it comes in contact with urine. This is a common myth.

Margot's house (62 Mackenzie Crescent) and Woodbine Beach are on opposite sides of Toronto's downtown, and walking the distance between them takes more than two hours. Sarah Polley acknowledged this inconsistency, saying "It's a romanticized, idealized Toronto where we would have access to the waterfront on [the west] side of town".