NRF

Global – October 21, 2026 -- The NRF 4-5-4 Calendar adds a 53rd week to the retail reporting year roughly every five to six years, most recently in 2023, to keep sales comparisons aligned between years.

Calendar splits the year into 4-5-4 week months to match weekends and holidays

The voluntary industry guide divides the year into months of 4, 5 and 4 weeks. Comparable months contain the same number of Saturdays and Sundays, so like days are compared with like days in sales reporting. The layout also lines up holidays.

The format dates to an informal inter-industry discussion in the 1930s. Retailers had reported on a straight calendar, but weekends made up a growing share of sales while the number of weekends per month varied from year to year. Many stores adopted the 4-5-4 Calendar in the 1940s.