bw wrote...
....
=IF(('Comparison Chart'!H63=“Select One”),“Select One”,
IF('Comparison Chart'!H63=“Monthly”),“Monthly”,
IF('Comparison Chart'!H63=“2.5% Discount Paid Quarterly”),“Quarterly”,
IF('Comparison Chart'!H63=“5.0% Discount Paid SemiAnnually”),“SemiAnnually”,
IF('Comparison Chart'!H63=“12.0% Discount Paid Annually”),“Annually”,"")

This isn't a syntactically valid formula. In your first IF call,
you've got *2* left parentheses after IF, which is good because you
have a right parenthesis just after the comparison. However, in all
the other IF calls, you have a stray right parenthesis after the
comparison but only one left parenthesis after IF, which Excel
interprets as trying to finish those IF calls with only one argument.
Since IF requires at least two arguments, that causes a syntax error.
And your missing all but one of the necessary right parentheses at the
end.

Rewrite your formula as

=IF('Comparison Chart'!H63=“Select One”,“Select One”,
IF('Comparison Chart'!H63=“Monthly”,“Monthly”,
IF('Comparison Chart'!H63=“2.5% Discount Paid Quarterly”,“Quarterly”,
IF('Comparison Chart'!H63=“5.0% Discount Paid
SemiAnnually”,“SemiAnnually”,
IF('Comparison Chart'!H63=“12.0% Discount Paid
Annually”,“Annually”,"")))))

And don't post formulas using “ and ” rather than ". If you're using
left and right double quote characters rather than the generic ASCII
double quote character, that would also cause syntax errors.