SQL Query to find the last day of the month

Solution 1:

Try this one -

CREATE FUNCTION [dbo].[udf_GetLastDayOfMonth] 
(
    @Date DATETIME
)
RETURNS DATETIME
AS
BEGIN

    RETURN DATEADD(d, -1, DATEADD(m, DATEDIFF(m, 0, @Date) + 1, 0))

END

Query:

DECLARE @date DATETIME
SELECT @date = '2013-05-31 15:04:10.027'

SELECT DATEADD(d, -1, DATEADD(m, DATEDIFF(m, 0, @date) + 1, 0))

Output:

-----------------------
2013-05-31 00:00:00.000

Solution 2:

I know this question was for SQL Server 2005, but I thought I'd mention- as of SQL 2012, there now is an EOMONTH() function that gets the last day of the month. To get it in the format specified by the original asker you'd have to cast to a datetime.

SELECT CAST(eomonth(GETDATE()) AS datetime)

Solution 3:

SQL Server 2012 introduces the eomonth function:

select eomonth('2013-05-31 00:00:00:000')
-->
2013-05-31