When we add 15% margin to all project costs then look back at the profit on the same project it is always lower than 15% thanks in advance

Hello there, @steve328.

I'm here to share how adding margin works in QuickBooks Online (QBO).

There could be several reasons why their P&L is lower than the 15% margin. One possible reason is that there's an additional expense that was not accounted for when the margin was added. Another reason is that incorrect or erroneous estimates may have led to a higher-than-expected project cost.

You can review the project cost and associated expenses to identify any discrepancies or areas where costs could be reduced.

Also, markup and margin have different calculations. Therefore, it's not necessarily that the two match. You can also pull up a Project Profitability Report to check the calculation.

Here's how:
 

1. Go to Projects on the left pane.
2. Double-click the project name.
3. Under Project reports, select Project Profitability.
4. Click Customize.
5. Filter the details you'd like to see.
6. Once done, click on Run report.

Please check this article to learn more about profit margins, this is a global website but it's applicable to all regions that use QBO: Net profit margin: Definition, formula, and example.
 

Furthermore, this article will show you how to use the project function in QuickBooks and track the profitability of your project: Set up and create projects in QuickBooks Online

Fill me in if you have other project-related concerns or questions. I'll jump right back in to respond to them. Enjoy the rest of the day.