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This tutorial will teach you how to calculate the first day of the month in Excel and Google Sheets.
Calculate First Day of the Month
There’s no Excel function to calculate the first day of the month, but the EOMONTH function will calculate the last day of a month.
To find the first day of a month we will calculate the last day of the previous month and add one day.
Here let’s find the last day of the previous month:
Now let’s add one day to the result:
You can also use the DAY Function to find the first day of the month:
=B3 - DAY(B3)+1
Here the DAY Function returns the day number of a date. By subtracting this from the current date (and adding 1) we arrive at the first day of the month.
Google Sheets Example
These formulas work exactly the same in Google Sheets as in Excel.