I don’t believe this is true (or false) in Power Automate child flows

Sometimes Power Automate can be difficult to understand. Today I’m looking at the how child flows handle the boolean values true and false.

True or false

Just to start this post I would like to make clear that true is not a text “True” and false is not “False”

Child flow output in Power Automate

I’ve created a simple flow that I will call from another flow. My child flow has two output parameters and both these parameters’ are Yes/No parameters.

Now when I call this flow I’m seeing:

So now when the parent flow uses the data returned by the child flow any Boolean comparison will fail unless you compare things with “True” and “False” or convert the string values back to true and false first.

Peek Code

When we have a peek at the code, we will see that the Respond to a PowerApp or flow gets things right and the Run a Child flow is at fault here.

I don’t have a good way to fix this in flows and I also wonder if Microsoft could even fix this issue as existing flows would break. Therefore hopefully this post will help a bit working around this issue.

As an alternative the Respond action could solve this problem, however that action is a premium action and may be avoided by many flow makers.

Pieter Veenstra

Is your business still running on paper trails, sprawling Excel files, or ageing Access databases? There's a better way — and I can show you exactly what it looks like. I'm the Technical Director of Vantage 365, a Microsoft solutions consultancy working with clients across the UK, the Netherlands, and worldwide. For over 30 years I've been turning messy, manual business processes into clean, automated systems that save time, reduce errors, and give teams the visibility they need to make better decisions. SharePains is not just any blog run by a Microsoft MVP. Have you ever used Try-Catch in Power Automate? The original post about Try-Catch in Power Automate can still be found on this site, https://sharepains.com/2018/02/07/try-catch-finally-in-power-automate-flow/ Or have you ever used the Pieter’s method to avoid variables and speed up your flows? https://sharepains.com/2020/03/11/pieters-method-for-advanced-in-flows/ You can contact me using contact@sharepains.com