An Oklahoma resident may deduct nonrecurring adoption expenses not to exceed $20,000 per calendar year. Expenses are to be deducted in the year incurred. "Nonrecurring adoption expenses" means adoption fees, court costs, medical expenses, attorney fees, and expenses which are directly related to the legal process of adoption of a child.

You should create a schedule describing the expenses claimed. If you are mailing your return then you should enclose the schedule with your tax return. If you are e-filing then you should retain the schedule in your records for three years.