According to the United States Internal Revenue Service (IRS) Pub 1771, a written disclosure statement is
required for membership benefits provided in exchange for an annual
payment of $76 or more (page 6).
While NARM benefits are offered
at the $100 level and above, a disclosure statement is not required
"where there is no donative element involved in a particular
transaction, such as in a typical museum gift shop sale" (page 12).
on the advice of Deputy General Counsel at the Smithsonian
Institute during the 2011 AMMC conference:
/Frequently used benefits, such as unlimited admissions (NARM), can be
difficult to value and a disclosure statement is not required.
IRS Publication 1771 Charitable Contributions Substantiation and Disclosure Requirement