We do not see any problems with allowing a customer to use a single deposit account for multiple businesses. From the facts you have given us, the customer’s businesses are all sole proprietorships—there are no legal entities that have an existence outside of the customer. For that reason, there should not be any issues with allowing the customer to deposit checks made out to different fictitious names into a single account.

Of course, your due diligence should include collecting documentation that the customer has fulfilled the Assumed Business Name Act for its d/b/a names, which include application and notice requirements. 805 ILCS 405/1.

Note that if your institution sets up sub-accounts for each sole proprietorship (referred to as “unincorporated associations”), each sub-account will be separately insured by the FDIC. 12 CFR 330.11(c).  

Also note that you may be required to aggregate the transactions of the customer, even if they are performed under different assumed names. See FinCEN Guidance, FIN-2012-G001 — Currency Transaction Report Aggregation for Businesses with Common Ownership (March 16, 2012). FinCEN has also released a ruling that details the CTR filing requirements as to sole proprietorships operating under an assumed (or “doing business as”) name. Ruling, FIN-2008-R001 — Reporting of Certain Currency Transactions for Sole Proprietorships and Legal Entities Operating Under a “Doing Business As” (“DBA”) Name (January 25, 2008).