Use the DateDiff function to get the difference. Since the function is
defined to return a Long (a large integer value) rather than a Single
or a Double, you can't use the "h" interval parameter if you need to
calculate fractions of an hour; you have to use the "n" parameter to
get minutes, and then compute hours:minutes from that number...

Sub demo()
   Dim startTime As Date, endTime As Date
   Dim diffHr As Long, diffMin As Long
   
   startTime = CDate("8:00 am")
   endTime = CDate("12:35 pm")
   diffMin = Abs(DateDiff("n", startTime, endTime))
   diffHr = Int(diffMin / 60) ' truncated to whole hours
   diffMin = diffMin Mod 60   ' remaining minutes
   MsgBox diffHr & ":" & diffMin
End Sub

--
Regards,
Jay Freedman
Microsoft Word MVP        FAQ: http://word.mvps.org
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