If they are being reimbursed, yes.  Especially at year end.  This is because you do not want to pick up the expenses if they are going to be reimbursed.  That would mean that the following year, you would be picking up income.  Best to set up an "Other Current Asset" account, on the balance sheet, it will track any expenses that have NOT been billed to your clients (accrual basis reporting) or reimbursed by your clients (cash basis reporting) as of the last day of the year.  This way they are just held in an account waiting for the reimbursement, and your books and taxes will not be affected.