I would like to use countif across multiple month tabs for an entire column. I can use the following format for sum and it works: =sum(jan:dec!b:b)
I can use countif for one tab and a whole column: =countif(Jan!b:b,"item")
When I use countif across multiple tabs I get a #value! error message: =countif(jan:dec!b:b,"item")
Is there a way to use countif the way I am trying to use it?

No.
COUNTIF cannot handle 3D references.

There may be a (quite involved) workaround (though not for whole columns) but it would require more info.

Thanks for the quick reply. Too bad countif has that limitation. Back to the drawing board.

See how this works for you...

=SUMPRODUCT(COUNTIF(INDIRECT("'"&MySheets&"'!B:B") ,"Item"))

List all your tab names and create a named range called MySheets

Thanks for your reply. I've tried several iterations to define a named range with tab names but I can't get the thing to work. I tried =Jan!ec! and ended up with Jan!:jan:dec (which gave me all columns from dec through jan on tab Jan). I tried Jan!,Feb!, through Dec! and got an error message. Is there a trick to listing all twelve tabs (Jan through Dec) in a named range? I would definitely appreciate any help you can give me with this naming convention.
Thanks for your help.

Why not :
group the tabs (click the first tab then the last while holding the Shift key)
enter the COUNTIF function in an occupied cell on the first sheet ( it will copy automatically to all sheets in the group)
Now on you master sheet use the SUM function with a 3D reference to obtain the final result
You can ungroup whenever needed

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See if this example helps...

http://www.contextures.com/xlNames01.html

Attached Files

marconexcel.xlsx (14.5 KB, 9 views)