The cost to change a ticket on Delta Airlines varies based on the fare type and route. For domestic flights, changes are typically free for Main Cabin and above fares, while Basic Economy tickets are usually non-changeable. International flight changes can incur fees ranging from $200 to $500, depending on the destination and fare class. Additionally, any fare difference between the original and new ticket must be paid. For specific fees, it\’s best to check Delta\’s official website or contact their customer service.
Source: https://medium.com/@delays/how-to-change-delta-airlines-flight-3e90b5c3eaab