Type in 1/1/07 in B1 and 15/1/07 (or 1/15/07) in C1, then in D1 enter
this formula:

=DATE(YEAR(B1),MONTH(B1)+1,DAY(B1))

Then copy this across row 1 for as many columns as you need.

You can have different start dates in B1:C1.

Hope this helps.

Pete

On Nov 18, 6:28 pm, wrote:
I recieve income on the 1st and the 15th of every month, regardless of
the month, or day.

Understanding the serial number feature of Excel, I cannot create a
autofill that will fill in the 1st and 15th of every month.

I need to be able to type in the 1st of a month then autofill across
and have it pick up the 1st and 15th of every month.

How can this be performed?