How to get free fries at McDonald's and Wendy's this week

McDonald's and Wendy's are both giving away free fries this week.

On Wednesday, in celebration of the (apparently real) National French Fry Day, McDonald's will give away free orders of large fries — with no purchase necessary. However, the free fries can only be ordered through the McDonald's app, and customers must be members of the chain's loyalty program.

Similarly, Wendy's (WEN) on Monday announced the beginning of Fry Week, during which the chain is offering free fries with specific purchases that will change each day this week. For example, on Tuesday Wendy's customers can get free medium fries with any salad purchase.