These calendars use a 13-week system in which the fiscal year consists of four equal quarters, each comprising 13 weeks (totaling 52 weeks). This structure is divided into accounting months following one of two fixed sequences:
- The 4-4-5 calendar includes two 4-week periods, followed by one 5-week period.
- The 4-5-4 calendar includes one 4-week period, followed by one 5-week period, then one 4-week period.
The calendars provide several benefits that improve comparability:
- The calendar lines up holidays.
- This format ensures that each month has the same number of Saturdays and Sundays, and the accounting weeks are standardized from year to year.
Weekends and holidays can generate spikes in revenue, and these calendars allow you to compare sales with more accuracy.
For a fiscal calendar starting in 2026, many organizations align the start around late January or early February (often beginning on a consistent weekday). The difference is seen in the number of weeks per month:
- 4-4-5 calendar: February (4), March (4), April (5)
- 4-5-4 calendar: February (4), March (5), April (4)
Each calendar has 13 weeks in the first three months of the year. To use these calendars, organizations typically adopt a fiscal reporting calendar aligned to weekly periods.
How to adopt a retail fiscal calendar
Adopting a 4-4-5 or 13-period calendar is often an internal operational shift rather than a formal change to your tax year. Many restaurant groups maintain a standard calendar year for the IRS while utilizing a fiscal week system for internal reporting, labor management, and P&L analysis.
This allows for precise weekly comparisons often without changing the federal tax year.
That said, if you choose to align your official tax year with your new fiscal calendar, you may need to file specific documentation with the IRS:
- Form 1128: Application To Adopt, Change, or Retain a Tax Year
- Form 8716: Election To Have a Tax Year Other Than a Required Tax Year
You also need to update your accounting system so that the software generates financial statements for the new fiscal year. For example, a fiscal calendar adopted in 2026 may result in a year-end that falls in late January rather than December 31.
Finance leaders must consult with their tax advisors to confirm the correct form and ensure adherence to all federal, state, and local requirements. This step is critical for maintaining compliance readiness.