Why do I have to file form 5500 and cannot file form 5500-EZ?

As a general rule, ERISA doesn’t cover solo plans, so you can file Form 5500-EZ. But if the plan has non-qualifying assets, you must file Form 5500. This is because there is no ‘solo participant plan’ election on the form, so the plan will qualify as a single-employer plan, thereby falling under the bonding rules.