Last summer's London Olympics and the Queen's Diamond Jubilee celebrations drove the Channel tunnel operator Eurotunnel to a record year in 2012.
Traffic records were broken over the summer, pushing net profits up almost 80 per cent to €34m (£22m) from €11m in 2011. As a result the board recommended boosting the dividend by 50 per cent to 12 cents a share.
But Jacques Gounon, the chief executive of the Paris-listed company, warned that growth on 2013 was unlikely to be as strong.
In a statement the company said: "Activity remains positive, but as 2012 benefited from some exceptional events, traffic is unlikely to see a repeat of 2012's strong growth, even with the British public taking more and more short breaks on the Continent via Le Shuttle."
Last year almost 20 million passengers and 20 million tonnes of goods used the Channel tunnel, and it reached a landmark 300 millionth passenger since it started commercial services in June 1994.
The company is still hoping that French and UK regulators will reach a compromise over Eurotunnel's proposed move into the cross-Channel ferry market. It splashed out €65m to take over three ships formerly owned by the Channel ferry company SeaFrance last year, to be operated by the Eurotunnel business MyFerryLink.
The move was cleared by the French competition watchdog but last month the Competition Commission said the business created "a substantial lessening of competition" in the market and recommended it be sold.
Mr Gounon said the company would appeal against a forced sale and said: "We are waiting for reasonable constraints."