Max wrote

Formula Is| =AND(TEXT(C4,"mmmm")=$C$2,C4<"")

Excellent!!! Reducing to =TEXT(C4,"mmmm")=$C$2 works as well, although I
can see why the test for blanks might come in handy someday.

Thanks.

P.S. While waiting for a response I was able to type 2/1 (that makes
changing months easier) in C2 and custom format as mmmm and achieve what I
wanted with:
Formula is|=MONTH(C4)=MONTH($C$2)
The secret was making C2 absolute, which I had overlooked in previous
trials.

--
David