Shane Bartholomeusz

Technical Solutions Consultant

Handling Excel Dates in Microsoft Power Automate


Dealing with dates can be a real pain in the proverbial sometimes … and Microsoft Power Automate (aka Microsoft Flow) is no exception.

I recently had to bulk load some records from an Excel file into SharePoint Online using Microsoft Power Automate … you'd be forgiven to think that this would be a trivial task … WRONG!

Microsoft Flow and Excel Logos

All was going well until … I encountered date fields in my Excel file … then all hell broke lose!

I was puzzled why Dates in my Excel file were processed by Microsoft Power Automate as numbers … what the? What's going on here?


The root problem is that Microsoft Power Automate reads Date columns as Text. Excel stores dates in Serial Date format which means that a date like ‘2019-01-10' will be read as ‘43475' within Power Automate.

You can read more about how excel handles dates here:

Therefore we need to convert the Number to a Date using the below expression within our Power Automate workflow

// Format
if(empty(<DATE TO CONVERT>),null,addDays('1899-12-30',int(<DATE TO CONVERT>),'yyyy-MM-dd'))
// Example
if(empty(item()?['Start Date']),null,addDays('1899-12-30',int(item()?['Start Date']),'yyyy-MM-dd'))


In this simple example I'll create a workflow to insert the contents of an Excel spreadsheet into a HTML table.

The flow contains the following steps:
1. Read rows from an Excel Spreadsheet
2. Insert each row into a HTML formatted table

Excel Worksheet Screenshot

I've added the below expression into the ‘FormattedDateCompleted' field of the HTML table.

if(empty(item()?['Timesheet Completed Date']),null,addDays('1899-12-30',int(item()?['Timesheet Completed Date']),'yyyy-MM-dd'))

Here is the output after running the workflow. You can see the original date value and the formatted date value.

Final Thoughts

Well I hope this solution has helped you. If you have any thoughts or alternative solutions feel free to post them in the comments below.

Shane Bartholomeusz


  1. Great Article! Thank a lot for your help!

  2. Hi Shane – I’m just getting into Flow. Where exactly did you make the change? Can it be made at the spreadsheet/table level ?

    • Shane Bartholomeusz

      4th November 2019 at 9:48 pm

      Hi Robert, you’ll need to create the Expression within Microsoft Flow via the popup menu that appears when you click a field/step in your Flow.

      Otherwise, (although I haven’t tested this) you could convert the ‘date’ formatted cell to a ‘text’ type field and it should import without issue.

  3. Hi Shane, Thanks for the tip but how to convert/format date and time?

  4. Shane,

    I thank you profusely for this! You have saved me a lot of head scratching!


  5. anybody here that can explain to me how to get this configured in Power Automate ?

  6. Great article! btw, how to create an expression if i have date and time in excel, (Example: 43924.04097)

  7. Sorry but this doesn’t work for me. I just get an error stating ‘The Expression is Invalid’. Any ideas what I need to check.

    • Shane Bartholomeusz

      19th July 2020 at 8:26 am

      Hi John,
      Thanks for pointing that out. I just realised there was a mistake in the expression, which I’ve now corrected.

      I’ve also included an example for reference. Hope that helps.

  8. Great. Thanks. I’ll take a look.

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