12 C.F.R. § 741.10
Any credit union which is insured pursuant to title II of the Act and is permitted by state law to accept nonmember shares or deposits from sources other than other credit unions and public units (or, for low-income designated credit unions, any nonmembers), shall identify such nonmember accounts as nonmember shares or deposits on any statement or report required by the NCUA Board for insurance purposes. Immediately after a state-chartered credit union receives notice from NCUA that its member accounts are federally insured, the credit union shall advise any present nonmember share and deposit holders by letter that their accounts are not insured by the NCUSIF. Also, future nonmember share and deposit fund holders will be so advised by letter as they open accounts.
12 C.F.R. §741.10