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Date.StartOfMonth is a Power Query M function that returns the start of the month that contains the specified date(Time). Your input must be a date or datetime value.

Compatible with: Power BI Service Power BI Desktop Excel Microsoft 365


Date.StartOfMonth( dateTime as any ) as any


Date.StartOfMonth determines the start of the month for a dateTime parameter (of type date, datetime, or datetimezone).


Find the start of the month for October 10th, 2011, 8:10:32AM.

// Output: #datetime( 2011, 10, 1, 0, 0, 0 )
Date.StartOfMonth( #datetime( 2011, 10, 10, 8, 10, 32 ) )

Learn more about Date.StartOfMonth in the following articles:

Other functions related to Date.StartOfMonth are:

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