Amid a rise in the number of passengers, Narita International Airport Corp. is making final arrangements for an additional fee to be levied on domestic travelers to upgrade services there, airport sources said Tuesday.

The passenger service facility charge — which covers the cost of using and maintaining facilities such as airport lobbies and the flight information system — is currently imposed only on passengers on international flights.

Arrangements are underway for passengers on domestic flights operated by the nation's two major airlines, Japan Airlines Co. and All Nippon Airways Co., to have ¥900 added to the cost of round-trip fares, and those flying on low-cost carriers will be expected to pay a smaller amount, the sources said.

The operator's move to impose such a fee comes at a time when the airport, a hub for several low-cost carriers, is seeing an increase in the number of domestic passengers.

Currently, an adult passenger departing Narita on an international flight has to pay a passenger service facility charge of ¥2,090. A fee of ¥1,050 is charged for passengers on connecting international flights.

This fee, which is also used to cover the expense of providing baggage carts and passenger information services, is included in the airfare when tickets are issued to travelers.

In fiscal 2013, the number of passengers who went through Narita was roughly 36 million, of which 5.2 million were on domestic flights.

Among measures to accommodate the increasing number of travelers at Narita, a passenger terminal exclusively for low-cost carriers is expected to be completed by the end of March.