Flights from Gatwick to Aktion airport will debut on 3 May, serving Preveza and Lefkada.
The budget carrier will operate the summer service twice-weekly on Sundays and Thursdays from 21 May until 1 October.
Fares will lead in from £60.50pp one-way.
The route is Norwegian's first to mainland Greece, and will complement the carrier's existing Rhodes, Santorini, Kefalonia and Crete flights.
Norwegian has also boosted capacity on a number of other European routes.
It will operate a second weekly flight to Crete, a new morning departure five days a week to Stavanger, and extra seasonal service to Tromso -- increasing to twice-weekly in April, May, September and October.
Magnus Maursund, Norwegian senior vice-president commercial short-haul, said the carrier was pleased to offer Brits "more choice and flexibility" when flying this summer.
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