Illinois has opted out of the federal bankruptcy exemptions,  
but the opt-out applies only to its residents. “[Residents of this
State shall be prohibited from using the federal exemptions
provided in Section 522(d) of the Bankruptcy Code of 1978
(11 U.S.C. 522(d)), except as may otherwise be permitted
under the laws of Illinois.” 735 I.L.C.S. 5/12-1201. So, if this
state is the applicable state (as determined by the method
stated on the home page of this site), debtors who are not
Illinois residents on the date of filing bankruptcy may use the
federal exemptions.  
Shell v. Yoon, 499 B.R. 610 (N.D. Ind.
2013) (Illinois has prohibited its residents, and no one else,
from using the federal exemptions);
In re George, 440 B.R.
164 (Bankr.E.D.Wis. 2010) (Illinois opt-out provision does not
prevent nonresident from claiming federal exemptions).

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