Primavera P6 Milestones
P6 Milestones are zero duration activity because it does not have duration. P6 has two activity types that mark an activity as a Milestone, they are Start Milestone and Finish Milestone.
- Start Milestone activity indicates the beginning of a phase in a project.
- Finish Milestone activity indicates the end of a phase in a project.
For Example, Starting P6 Tutorial is an example of Start Milestone, and Completing the P6 Course is an example of Finish Milestone.
For a standard 5days Calendar with working time 8 AM to 5 PM. The Start Milestone starts at 8 AM & the Finish Milestone ends at 5 PM by default. Also, the Start Milestone does not have finish date & Finish Milestone does not have a Start Date. In this section, we walk through on the following topics
1. How to define a Milestone
2. Start and Finish dates in a Milestone
3. Supported Milestone constraints
4. Supported Milestone Relationships
5. Resource or Role Assignment in a Milestone
6. Add cost to a Milestone
How to define a Milestone?
1. Open a Project, Go to Activities tab, Select an Activity, Select the General tab, Choose either Start Milestone or Finish Milestone. A black diamond symbol on the Gannt chart represents the milestone.
Start and Finish Dates in Milestone
Start Milestone accept only Start Date, and Finish Milestone accept only Finish date. As shown in the below image, the Finish date is empty for a Start-Milestone activity & Start date is empty for a Finish-Milestone activity
Supported Milestone Constraints
Start Milestone does not support any constraint that contains Finish. Look at the below image; I tried to set a constraint Mandatory Finish on Start milestone activity, P6 throws an error message ‘Invalid Constraint’
Finish Milestone does not support any constraint that contains Start.so the
Supported Constraint types of Start Milestone = As Late as Possible, Mandatory Start, Start On, Start On or After, Start On or Before
Supported Constraint types of Finish Constraint = As Late as Possible, Mandatory Finish, Finish On, Finish On or After, Finish On or Before
Supported Milestone Relationship
As I mentioned earlier, the Start Milestone does not have Finish date and meant be only started, so only the following relationship types are supported for a start Milestone activity if the predecessor & successor are other than a Milestone
As I mentioned earlier, the Finish Milestone does not have Start date and meant to be only finished, So only the following relationship types are supported for a Finish Milestone if the predecessor & successor are other than a Milestone
What happens if a Predecessor and successor are also milestones? Let’s Play with three milestones
The below table summarize the supported Relationship types that we described above
|Predecessor||Successor||Relation Ship Type|
|Task-Dependent/ Level of Effort/
|Start Milestone||Finish to Start/ Start to Start|
|Task-Dependent/ Level of Effort/
|Finish Milestone||Finish to Finish/ Finish to Finish|
|Start Milestone||Start Milestone||Start to Start|
|Finish Milestone||Start Milestone||Finish to Start|
|Start Milestone||Finish Milestone||Start to Finish|
|Finish Milestone||Finish Milestone||Finish to Finish|
Does P6 Milestones Support Resource / Role Assignment?
P6 Start or Finish Milestone does not support Resource or Role Assignments. The Assignment button is disabled for a milestone. It may have a Primary resource.
What if I want to add cost to a P6 Milestones?
As it does not support Resources Assignments so we cannot add a cost through assignments. Use the Expenses to add cost to a Milestone
Please share your comments below if you have any questions on P6 Milestones.