Definition of Microsoft Project constraints

Summary

Each constraint type in Microsoft Project can be defined as a formula using the following conventions:

ES = Early Start of the activity

LS = Late Start of the activity

EF = Early Finish of the activity

LF = Late Finish of the activity

SS = Scheduled Start of the activity

SF = Scheduled Finish of the activity

CD = Constraint Date

More Information

The following are definitions of Microsoft Project constraints.

  • As Late As Possible: Schedules the task as late as it can without delaying subsequent tasks. Use no constraint date.

    ES=(Calculated)LS

  • As Soon As Possible: Schedules the task to start as early as it can. Use no constraint date.

    (Scheduled)ES=(Calculated)ES + Delay

  • Finish No Earlier Than: Schedules the task to finish on or after the constraint date.

    EF=CD (if Date<EF)

  • Finish No Later Than: Schedules the task to finish on or before the constraint date.

    LF=CD (if Date<LF)

  • Must Finish On: Schedules the task to finish on the constraint date. Once selected the task will not be moveable on the timescale.

    EF,LF,SF=CD

  • Must Start On: Schedules the task to start on the constraint date. Once selected the task will not be movable on the timescale.

    ES,LS,SS=CD

  • Start No Earlier Than: Schedules the task to start on or after the constraint date.

    ES=CD(if Date<ES)

  • Start No Later Than: Schedules the task to start on or before the constraint date.

    LS=CD(if Date<LS)