The Broadcast Calendar is a Monday-start calendar used by US broadcasters and ad-buying systems for inventory, billing, and audience reporting. It is published annually by the Nielsen-aligned Broadcast Calendar reference and used industry-wide.
How the broadcast week works
The broadcast week runs Monday through Sunday. Every broadcast week contains exactly 7 days, with no short weeks.
How the broadcast month works
A broadcast month begins on the Monday containing the 1st of the calendar month. Days from the prior calendar month that fall in that opening week are counted in the new broadcast month. The previous broadcast month therefore absorbs any leftover days at its end. Each broadcast month contains either 4 or 5 broadcast weeks.
Difference from other week standards
The broadcast calendar differs from ISO 8601 and US week numbering in 2 ways:
- Month definition — broadcast months are week-aligned, not date-aligned.
- Year length — a broadcast year contains 52 or 53 broadcast weeks.
CBS, NBC, and major ad agencies cite the broadcast calendar for spot scheduling and post-log reconciliation. Audience-measurement firms including Nielsen and Comscore deliver ratings on the same week boundaries.