Gantt Chart Tips: When to Use Milestones in Your Project Plan


Gantt Chart Tips: When to Use Milestones in Your Project Plan

Life is full of milestones – and so are projects.  When planning a project, aside from laying out the tasks that take you from beginning to end, you’re inevitably going to want to mark key dates along the way.  One easy way to do this is through the use of a diamond shaped symbol in your Gantt chart, the milestone.  Milestones not only help your team stay on track, they are also useful to you as a project manager to more accurately determine whether or not your project is on schedule. 

Incorporating milestones in your project planning helps you and your team keep sight of:

  • Key Dates  Launch parties, board meetings, product rollouts and other key dates mark significant pieces of your project.  It’s also helpful to include other one-day events unrelated to your project specifically that are still important for your team to keep in mind – like a group offsite or team holiday.
  • Key Deadlines  Key deadlines are important to surface on large project plans so your team can easily see what’s coming up and plan accordingly.  For example, the date that website development is completed or when customer conference registrations need to be returned to qualify for early bird pricing. Key deadlines are related directly to your project but they aren’t project tasks.  Use a key deadline as a milestone to reflect when a section of tasks or key task is completed.
  • External Dates and Deliveries For example, a due date for a deliverable you are expecting from an agency,  the date when your hiring manager has received an offer letter, or the day that pipes are scheduled to be delivered.  These key events can affect when other tasks in your project are allowed to start.  They may also be used as predecessors in your plan.

How to create a milestone:

A milestone is an important date or event that you can include in your project sheets, reflected as a diamond symbol in your Gantt charts.  

  • Make sure your project sheet has Dependencies enabled.
  • On a new row in your project, write a brief description of your milestone in the task name column (‘Company Off Site’, ‘Registration Materials Due’, etc).
  • In the Start Date column, enter the date of your milestone.
  • Enter a Duration of zero.

If you’re looking to start planning with milestones, this basic project template is pre-built with dependencies, perfect for getting started.

Just another way to keep your team organized and on track.  How are you using milestones? Let us know!

Til next week, dig in and explore!

- Support Team

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In the successor of the milestone, lag the milestone by 1 day or change the dependency from the default FS (Finish-to-Start) to SS (Start-to-Start).

Zero Duration does not mean, the time spent on processing the perticular task is zero secs/Mins/Hrs/Days. But this perticular task is to be dealt as priority task and it has to be taken up as on when it pops up in your assignment list. Fear factor to be the completion on delivery mode and how quickly the task is accomplished on the same bussiness day or minimum number of business days. More precisely the same task is deligated to the workman with maximum efficiency. Your example of planning backwards shows a sample plan for preparing for a Halloween party. Since your 0 duration milestones actually take 1 day, your example has the person putting on their costume on 30-October !!! One day before the party ! Is there any way to fix this? Joey ( I'm in the process of evaluating smartsheet and this is clearly a showstopper.

Hi Joey and Stuart, In a circumstance where you would like a 0 duration for your milestone, using a lag day instead will work. Here's more information about lag days: Please email us at if you have any other questions, happy to help you both! Best, Kelly

Hi Justine, Unfortunately, recurring milestones aren't currently possible in Smartsheet. I've shared your question with our Product team to consider for product enhancements in the future. Thanks! - Kelly

Hello Michael, Every vote helps. We have submitted yours (for recurring milestones) to the product team for consideration. Thanks for your time and feedback! You can follow the product roadmap here:

Please add one more vote for recurring milestones. In a project calendar these are invaluable and it is very tedious inputting requirements again and again and again... Thanks! n

Is there a way to change the colour of the milestones? I would like to allocate a different colour of client milestones and our milestones.

Agreed - need to change color of milestones to reflect to which team the milestone is relevant. Thanks!

Hi there, The default milestone color is currently the only available option, though you can change the Gantt bar colors. I've shared your suggestion with our Product team to consider in the future. Thanks much, Kelly

Hi there, At this time, there is no capability to change the color of the milestones. As a workaround, you could change the duration to 1, then change the color of the 1-day Gantt bar. I've also sent your request to our Product team for future consideration. Thanks, Diana

I am looking to mark a monthly review of the costings on a construction project, but I dont want to have lots and lots of extra rows for each milestone. Is there a way to create something every 4 weeks in the same row??

Hi Pete, You can schedule recurring update requests for a monthly recurring task. While this will help your project team stay on track, it won't show up as a recurring milestone in your Gantt chart. I've shared your request for recurring milestones with our product team. Thanks! Kelly

i agree. This is critical to a marketing calendar in which many things happen more than once (monthly, quarterly etc.) When can this be made available. I know it is available in project. Thank you, Tere

Hi Kylie, I don't have any update on timing, though we've heard from many customers recently the need for recurring tasks and it is top of mind for our product team. Scheduling a recurring update request is one work-around, or if your whole team has access to the sheet, you can schedule a recurring reminder on the same task. Thanks! Kelly

Hi Joey and Stuart, In a circumstance where you would like a 0 duration for your milestone, using a lag day instead will work. Here's more information about lag days: Please email us at if you have any other questions, happy to help you both! Best, Kelly

Kelly, there are two solutions for this problem, assigned SS to predecessor number is one, entering 1 into the Lag (Days) field is the other. I suppose the correct is the Finish-to-Start relationship occurs the same day by default !!!! Is logic !!!! Its a waste of time change all the relationships, always !!!

Hi Christian, Thanks for sharing your feedback – you're right, the dependent task is always scheduled to take place the next working day. I've passed your thoughts along to our product team to consider as we scope out updates and enhancements to the product. Thanks! Kelly

I am trying to use milestones to indicate site visits within a long construction schedule. I figure I have set the milestone as dependent to the overall construction event that is set for a duration of many months using Start to Start, however when I go to set the lag days, for the milestone my only option is to enter the number of days of lag. I would like the option to have a calendar pop up so I can just choose a date for the milestone. Thanks, Marc

It is really essential to get suitable tips for a successful project; therefore in every organization we have found professionals are always looking for better and suitable opportunities to make success their project structure. But due to lack of professional tips sometimes they are unable to deliver quality of result and successful projects. Therefore they should follow certain tips from here in order to develop a successful project in their organization.

Hi, I have the same sequence of tasks and meetings that occur on a relative basis, and rather than keep repeating the same information in multiple rows in the sheet is there anyway I can make one line show many instances of the same tasks - e.g. monthly steering? Thanks. Mark

Hi Mark -- Smartsheet does not currently support recurring tasks. If you'd like to be reminded of a task on a recurring basis, you could set up a recurring update request. Best, Emily

Hello, We are trying to create a Project Management Schedule for the building of HYDRALADA machines (elevating work platforms). We use the Parent Row for 1 machine and a child row for each task that is required to complete that machine (there are 8 tasks per machine). We sometimes have up to 40 machines on order which produces the need for some serious scheduling. Also to add to this complicated task we have customers requesting the machines to be completed by a certain time (delivery date). Therefore we require a row/column that is set and does not change. We would like to be able to insert a machine (Parent Row) with the 8 tasks (Children Rows) and set the delivery date (date customer requires machine by) and have the whole production schedule automatically 'reshuffle' WITHOUT changing any of the pre-set delivery dates for any of the other machines. Then we should be able to see the number of hours required by staff members to be able to meet these deadlines OR see what less important delivery dates we will have to change to meet other more important delivery dates. Then we would be able to provide our customers with realistic dates of when their machine/s will be ready for delivery. We are having a lot of difficulty setting up a Project Schedule on Smartsheet to suit the above constraints. Can you please help?

Hello Susan, If you mark milestones as Smartsheet recognizes them (same start/end date and duration on 0) then you can filter by the duration column to show only tasks with a duration of 0. Hope this helps! Thanks, - The Smartsheet Team

Hello Mike, this is done with a predecessor. Add the row number of the proceeding task. See this article for help: –Thanks! The Smartsheet Team

Hi, I'd like to make the next parent task dependent on the milestone above. e.g. milestone marks a delivery in the production process, the next parent task (and subsequent child tasks) can't begin until the delivery is complete (and if the delivery/milestone is late the next stage needs to adjust accordingly). When I try and do this, all the child tasks under the parent task lined with the deliver/milestone revert to the same start date as the parent task (or first child). Is there a way to do this? The child tasks don't need to be dependent upon one another, but can't all start at the same time. Thanks

Hello Clare, Child tasks are auto-rolled up to parent tasks. If the parent tasks is linked to another task, it will force the child rows to be rolled up as well. We do not recommend adding a milestone to a parent row. Instead, add it to the first (date-wise) child task under the parent. That should provide the solution you are looking for. Thanks! - The Smartsheet Team

Is there a way to insert a milestone without enabling dependencies? I do not need that gray bar running along the screen but I need to use the milestones to mark meeting dates. Thanks!

Hi Emily, As milestones are created when a task has a 0 day duration, (and durations aren't available when dependencies are not enabled), there is not currently a way to have a milestone with dependencies disabled. We will send your requested feature to the product team for consideration. Regards, The Smartsheet Team

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