35 ILCS 5/302: Compensation paid to nonresidents.

(a) In general. All items of compensation paid in this State (as determined under Section 304(a)(2)(B)) to an individual who is a nonresident at the time of such payment and all items of deduction directly allocable thereto, shall be allocated to this State.

(b) Reciprocal exemption. The Director may enter into an agreement with the taxing authorities of any state which imposes a tax on or measured by income to provide that compensation paid in such state to residents of this State shall be exempt from such tax; in such case, any compensation paid in this State to residents of such state shall not be allocated to this State. All reciprocal agreements shall be subject to the requirements of Section 2505-575 of the Department of Revenue Law (20 ILCS 2505/2505-575).

(c) Cross references.

(1) For allocation of amounts received by nonresidents from certain employee trusts, see Section 301(b)(2).

(2) For allocation of compensation by residents, see Section 301(a).