Sales and passenger numbers at Eurostar grew in the first half of the year, boosted by a rise in US travellers.
Revenue in the six months to June rose 4% on a year ago to £421m. Passenger numbers increased by 3% to 4.7 million.
Growth was particularly strong given that last year's figures benefited from increased revenues resulting from the ash cloud disruption, Eurostar said.
The number of international passengers rose by 21%, driven in part by a "strong increase" in those from the US.
Commenting on the ash cloud disruption, which grounded airlines across Europe, Eurostar chief executive Nicolas Petrovic said: "It really helped us because many people tried our service who had never tried it before.
"Our key selling point against airlines is convenience, comfort, and the ability to work on board," he told the BBC.
Excluding the positive impact of the ash disruption on the figures for 2010, when Eurostar ran 70 extra trains and carried 100,000 extra passengers, the company said underlying revenues were 12% higher.