It takes potatoes approximately two to five weeks to expire according to Eat by Day. The exact amount of time it takes for potatoes to expire depends on a number of factors, including the type of potato and storage method.
Russet and white potatoes tend to have the longest shelf lives among potatoes. Typically, russet and white potatoes last around three to five weeks in the pantry and three to four months in the refrigerator. Yukon Gold, red, new and fingerling potatoes have shorter shelf lives. These potato varieties typically last around two to three weeks in the pantry and two to three months in the refrigerator. Baked potatoes, cooked potatoes and mashed potatoes last around a week when refrigerated. However, these potato products can last around six to eight months when frozen. Instant potatoes have a pantry life of up to one year.