Mixing of retirement plan assets that may be required to be maintained separately for certain reasons. For instance, adding regular IRA contributions to a conduit IRA is commingling, and results in the account losing it’s ‘conduit’ status.
Commingling is also used to refer to combining IRA assets with qualified plan assets, combining retirement plan assets with non-retirement plan assets.
IRC § 408(a)(5)
Additional Helpful Information
IRC § 408(a)(5) provide that “The assets of the trust will not be commingled with other property except in a common trust fund or common investment fund.”