# How do I auto-checkmark based on a date column and a end of month rule?

Hello. I have a checkbox column that I would like to have automatically checked when a rule is met. I'm unfamiliar with how to write this formula though. I will be using this to identify month end instances.

This will be using 3 columns - Date Column 1, Date Column 2, Checkbox Column 1.

Date Column 1 is the original date.

Date Column 2 is using this Workday formula =WORKDAY([Date Column 1]@row, 8) based on the original date found in Date Column 1.

Checkbox Column 1 is where I would like it to automatically checkmark if Date Column 2 is the last day of the month that Date Column 1 falls within or is any date in the following month.

Thank you for your help.

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This approach takes advantage of the MONTH function to compare the two dates. If the Month's are different with Date 2+ 1, it would indicate it was the last day of the month.

=IF(MONTH([Date column 2]@row + 1) > MONTH([Date column 1]@row), 1)

Does this work for you?

Kelly

• ✭✭✭✭✭✭

This approach takes advantage of the MONTH function to compare the two dates. If the Month's are different with Date 2+ 1, it would indicate it was the last day of the month.

=IF(MONTH([Date column 2]@row + 1) > MONTH([Date column 1]@row), 1)

Does this work for you?

Kelly

• @Kelly Moore This suggestion worked perfectly. Thank you!

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