The permanent change, which comes into effect from 2023, applies to 14 regional airports across the UK and Ireland including Manchester, Birmingham, Edinburgh, Belfast and Dublin.
Supplements will be removed on bookings made from Monday (22 August).
Riviera will operate more than 1,300 regional flights next year to serve cruise itineraries for the Seine, Rhone, Douro, Rhine and Danube, and touring holidays to France, Spain, Italy, Germany, Norway and Iceland.