Please Note: This article is written for users of the following Microsoft Excel versions: 97, 2000, 2002, and 2003. If you are using a later version (Excel 2007 or later), this tip may not work for you. For a version of this tip written specifically for later versions of Excel, click here: Automatically Advancing by a Month.

Automatically Advancing by a Month

by Allen Wyatt
(last updated March 13, 2015)

Jim has a need to advance the date in a particular cell by one month at midnight on the 14/15 of each month (00:00:00 on the 15th), and he wondered how it could be done.

As with many problems in Excel, the answer depends on the nature of the data involved and exactly what you want to do. If the date in the cell is today's date, and you simply want to have the cell display the current month up through the 14th, and then next month after that, then you can use a formula such as the following:

=CHOOSE(IF(DAY(NOW())>14,MONTH(NOW())+1,MONTH(NOW())),
"January","February","March","April","May","June",
"July","August","September","October","November",
"December","January")

This formula returns the name of a month, not a date. If you prefer to have a date returned, you can use this formula:

=IF(DAY(NOW())>14,DATEVALUE(IF(MONTH(NOW())=12,1,
MONTH(NOW())+1) & "/" & DAY(NOW()) & "/" & IF(MONTH(
NOW())=12,YEAR(NOW())+1,YEAR(NOW()))),NOW())

Both of these formulas account for the "end of year wrap-around" when you advance from December to January. A shorter version of this last formula can be created if you use the DATE function instead of the DATEVALUE function:

=DATE(YEAR(NOW()),MONTH(NOW())+((DAY(NOW())>14)*1),1)

This formula, unlike the DATEVALUE example, always returns a date that is the first day of any given month.

If you really want to advance the value of a particular date in a cell, then you must use a macro to do the task. Further, you must make sure that the macro only runs once a month, at a particular time on a particular day. For instance, if you wanted the macro to run at 00:00:00 on the 15th of each month, you would need to set up the macro so that it checked the date and time, and then ran at that particular date and time. You would also need to make sure that the workbook containing the macro was open over that date and time.

The following macro will fetch the date from a cell and increase it by a month. The macro assumes that you have a named range, DateCell, which refers to the cell to be updated.

Sub IncreaseMonth()
    Dim dDate As Date
    dDate = Range("DateCell").Value
    Range("DateCell").Value = _
      DateSerial(Year(dDate), _
      Month(dDate) + 1, Day(dDate))
End Sub

To make sure that the macro runs at the appropriate time, you would need another macro. The following macro is designed to be run whenever the workbook is opened:

Private Sub Workbook_Open()
If Day(Now) = 14 Then
    Application.OnTime ("23:59:59"), "IncreaseMonth"
End If
End Sub

Notice that this particular macro sets the OnTime method so that it runs the IncreaseMonth macro at 23:59:59 on the 14th. This date and time was chosen because it is easier to catch than is 00:00:00 on the 15th.

Remember that the IncreaseMonth macro will only run if you open the workbook on the 14th, and then leave the workbook open until the 15th.

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (2180) applies to Microsoft Excel 97, 2000, 2002, and 2003. You can find a version of this tip for the ribbon interface of Excel (Excel 2007 and later) here: Automatically Advancing by a Month.

Author Bio

Allen Wyatt

With more than 50 non-fiction books and numerous magazine articles to his credit, Allen Wyatt is an internationally recognized author. He  is president of Sharon Parq Associates, a computer and publishing services company. ...

MORE FROM ALLEN

Setting a VBA Variable From a Bookmark

Bookmarks are quite helpful in a document. You may want to transfer the contents of a bookmark into a macro variable in order ...

Discover More

How Excel Treats Disk Files

Workbooks are loaded from disk files, but workbooks aren't the only type of files that Excel can load. This tip provides a ...

Discover More

Adding a Drop Shadow to a Text Box

One way to make your text boxes "stand off" the page is to add a drop shadow to them. This tip shows just how easy it is to ...

Discover More

Create Custom Apps with VBA! Discover how to extend the capabilities of Office 2013 (Word, Excel, PowerPoint, Outlook, and Access) with VBA programming, using it for writing macros, automating Office applications, and creating custom applications. Check out Mastering VBA for Office 2013 today!

MORE EXCELTIPS (MENU)

Specifying Different Weekends with NETWORKDAYS

The NETWORKDAYS worksheet function can be used to easily determine the number of work days (Monday through Friday) within a ...

Discover More

End-of-Month Calculations

Don't want to use the EOMONTH function to figure out the end of a given month? Here are some other ideas for discovering the ...

Discover More

The EDATE Function

Want to figure a date a certain number of months in the future or past? The EDATE function may be just what you need for your ...

Discover More
Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

View most recent newsletter.

Comments for this tip:

There are currently no comments for this tip. (Be the first to leave your comment—just use the simple form above!)

This Site

Got a version of Excel that uses the menu interface (Excel 97, Excel 2000, Excel 2002, or Excel 2003)? This site is for you! If you use a later version of Excel, visit our ExcelTips site focusing on the ribbon interface.

Subscribe

FREE SERVICE: Get tips like this every week in ExcelTips, a free productivity newsletter. Enter your address and click "Subscribe."

(Your e-mail address is not shared with anyone, ever.)

View the most recent newsletter.

Links and Sharing
Share