Date.AddMonths

Date

Adds a specified number of months to a date value.

Syntax

Date.AddMonths(dateTime as any, numberOfMonths as number) as any

Parameters

Name	Type	Required	Description
`dateTime`	`any`	Yes	The date, datetime, or datetimezone value to add months to.
`numberOfMonths`	`number`	Yes	The number of months to add. Use negative values to subtract months.

Return Value

any — The date resulting from adding the specified number of months to the input date.

Remarks

Date.AddMonths adds or subtracts a whole number of months from a date, datetime, or datetimezone value. If the resulting day would exceed the number of days in the target month, the day is clamped to the last day of that month (e.g., adding 1 month to January 31 yields February 28 or 29).

Examples

Example 1: Add 3 months to each OrderDate

Table.AddColumn(
    Table.SelectColumns(
        Table.FirstN(Sales, 5),
        {"OrderID", "OrderDate"}
    ),
    "Plus3Months", each Date.AddMonths([OrderDate], 3), type date
)

Result

	OrderID	OrderDate	Plus3Months
1	1	1/15/2024	4/15/2024
2	2	1/18/2024	4/18/2024
3	3	2/1/2024	5/1/2024
4	4	2/10/2024	5/10/2024
5	5	3/5/2024	6/5/2024

Example 2: Subtract 1 month from a date

#table(
    type table [OriginalDate = date, PreviousMonth = date],
    {{#date(2024, 3, 31), Date.AddMonths(#date(2024, 3, 31), -1)}}
)