Commissions paid to buy and sell investments are included in the cost of the investment for figuring gains and losses upon sale. If the commissions are for asset management fees, including commissions on investment trades, the commissions can be deducted the year they are paid. If the asset management fees, combined with other investment expenses, don’t exceed the 2% floor on miscellaneous itemized deductions, the expenses can be capitalized and added to the basis of the investment.