Date.AddDays - Date Function

Date.AddDays is a function in the Power Query M language that adds a specified number of days to a date or datetime value. The resulting value is returned as a date, datetime, or datetimezone.

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

Syntax

Date.AddDays(
   dateTime as any,
   numberOfDays as number,
) as any

Description

The Date.AddDays function allows you to add a specific number of days to a given dateTime argument. This argument can be of type date, datetime, or datetimezone. The function includes a numberOfDays argument, which specifies how many days you want to add (or subtract) to the given dateTime value.

Examples

Adding Days to a Date

Let’s start with a simple example. We want to add 10 days to the date of June 1, 2024. Here’s how we do it:

Date.AddDays( #date( 2024, 6, 1 ), 10 ) // Output: #date( 2024, 6, 11 )

In this example, the Date.AddDays function takes a date value as input and adds 10 days to it. The result is June 11, 2024.

Subtracting Days from a Date

Despite its name, Date.AddDays can also subtract days from a date. Let’s see an example where we subtract 10 days from June 1, 2024:

Date.AddDays( #date( 2024, 6, 1 ), -10 ) // Output: #date( 2024, 5, 22 )

Here, the function shifts the date back to May 22, 2024, by subtracting 10 days.

Adding Days to a DateTime Value

The Date.AddDays function is versatile and can also work with DateTime values. Let’s add 10 days to a specific date and time:

// Output: 6/11/2024, 12:00:00 PM
Date.AddDays( #datetime( 2024, 6, 1, 12, 0, 0 ), 10 )

In this case, the input and output are both DateTime values. The function adds 10 days to June 1, 2024, at 12:00 PM, resulting in June 11, 2024, at the same time.

Adding Days to a DateTimeZone Value

You can even use the Date.AddDays function with DateTimeZone values. Here’s how you can add 10 days to a DateTimeZone value:

// Output: 6/11/2024, 12:00:00 PM +02:00
Date.AddDays( #datetimezone( 2024, 6, 1, 12, 0, 0, 2, 0 ), 10 )

In this example, the function takes a DateTimeZone value as input and adds 10 days to it. The result is June 11, 2024, at 12:00 PM, with the same time zone offset of +02:00.

Learn more about Date.AddDays in the following articles:

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Other functions related to Date.AddDays are:

Contribute » | Contributors: Rick de Groot
Microsoft documentation: https://learn.microsoft.com/en-us/powerquery-m/date-adddays