No, they don’t. However, you may have a non-refundable service charge deducted from the total amount if you don’t use the money order within a certain timeframe. Usually, that period is between one and three years. Any penalties depend on the laws in the state where the money order was purchased.
You can find the terms and conditions of your money order listed on the back, so make sure you check any limits placed on yours to avoid paying a charge.
If your money order is subject to a non-refundable service charge, you won’t be able to present the order for payment after the specified time. Your order will come back to you unpaid, and you’ll need to request a refund for the balance remaining.