The only guide you need to understand calendars in P6

One of the most overlooked aspects of project control is the calendar setup.

Assigning the right working hours to each party - contractor, consultant, and procurement - can completely change the accuracy of your schedule.

For example:

Contractor calendars often run six days per week, covering construction and engineering submissions.

Consultant and authorities calendars may be five days per week, impacting inspections and approvals.

Procurement and curing activities require seven consecutive calendar days, not just working days.

Ignoring these differences can distort your schedule. A task planned on a weekend when the consultant is off will immediately shift dates, creating delays that aren’t visible until it’s too late.

By customizing calendars for each party, Primavera reflects reality - weekends, non‑working days, and continuous processes so your baseline and updates are truly comparable.

Calendars are not just settings. They are the foundation of realistic scheduling and practical plans.