Ill. Admin. Code tit. 74 § 722.570
The ABLE Program shall provide safeguards to prevent aggregate contributions on behalf of a designated beneficiary in excess of the limit under 23 Ill. Adm. Code 2500.90 pursuant to Section 529(b)(6) of the Code. As permitted under Section 1.529 A-2(g)(3)(ii) of the Treasury Regulation, the ABLE Program will comply with this requirement by refusing to accept any additional contributions to an ABLE account, except as otherwise permitted by Section 1.529A-2 of the Treasury Regulation, while the aggregate account balance in that account equals or exceeds the limit established by the State under 23 Ill. Adm. Code 2500.90 pursuant to Section 529(b)(6) of the Code. Once the aggregate account balance falls below that limit, additional contributions may again be accepted, subject to the annual contribution limit described in Section 722.560 of this Part. For purposes of this Section, aggregate contributions include contributions under any prior qualified ABLE program of any state or agency or instrumentality of either.
Ill. Admin. Code tit. 74, § 722.570