Form 5500 instructions:
Line 2i(4). Other expenses are those that cannot be included in 2i(1) through 2i(3). These may include plan expenditures such as salaries and other compensation and allowances (e.g., payment of premiums to provide health insurance benefits to plan employees), expenses for office supplies and equipment, cars, telephone, postage, rent, expenses associated with the ownership of a building used in the operation of the plan, all miscellaneous expenses and trustees’ fees and reimbursement of expenses associated with trustees such as lost time, seminars, travel, meetings, etc.