Emerald Waterways has scrapped its single supplement charge on five selected European itineraries in 2020.
Five cabins will be set aside for single passengers who not be required to pay the additional charge.
Customer feedback and trade interest prompted the line to launch its 2020 single supplement offer early.
The line has also issued a reminder about 14 departures remaining in 2019 across five additional itineraries where the single supplement has also been waived.
Emerald Waterways launched its new Star-ship vessel Emerald Harmony last month on the Mekong river.
More: Emerald Waterways releases details of new Mekong vessel
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The 84-passenger vessel will be the first to the fleet to eliminate single-use plastics.