Well, according to the Delta Airlines Flight Change Policy, the passengers are required to make changes in their flight within 24 hours of making their reservation. But, you are only have to pay when you have surpassed the limit of 24 hours. In this case, the fee can go from 75 to 200, all across the United States. The price can go up if you are on International flight. Usually, the prices ranges between $200 to a whopping number of $500. However, there are other factors too that plays an important role such as; fare class, ticket type and your departing destination.