As stated in this IDFPR Interpretive Letter (98-12), the Illinois Banking Act does allow the bank to pledge assets to secure deposit accounts, but you should contact the FDIC to see if you need the FDIC’s written consent before pledging any assets.

Where a state bank has a power that a national bank does not have, the FDIC must give its “prior written consent” before the state bank may use that power. 12 CFR 362.3(b). The Illinois Banking Act has been amended to allow state-chartered banks to pledge assets to secure any funds, and this power is no longer restricted to securing public funds. 205 ILCS 5/7(25)(a) (giving Illinois banks the same powers as Illinois savings banks); 205 ILCS 5/1008(a)(13)(B) (giving Illinois savings banks the power to “secure deposits”). But, as your research showed, national banks do not have the power to pledge securities to secure deposit accounts (with an exception for public funds). Texas & Pacific Railway Company v. Pottorff, 291 U.S. 245 (1934); FDIC Advisory Opinion 97-1 (January 6, 1997). Therefore, we believe the FDIC requirement of prior written consent would apply before the bank can pledge securities to secure consumer deposits. The FDIC has informed the IBA that it has removed all of its advisory opinions from its website due to a high risk of staleness. We have provided links to archived versions of the advisory opinions for your convenience. If you have a question about an advisory opinion, the FDIC recommends that you contact your FDIC Field Office, which you can find by clicking here.