Carrying an increased number of American, Brazilian and Australian travellers, Eurostar saw its operating profit rise from £25.0 million in 2011 to £52.3 million in 2012.
In total, the company carried 9.9 million passengers last year compared with 9.7 million in 2011.
Passenger numbers were strong after the Olympics, with traffic up 5% in the last three months of last year compared with the October-December 2011 period.
While business passenger number remained flat last year, the leisure travel market rose 3%. Non-EU passenger numbers grew 8% in 2012.
Eurostar chief executive Nicolas Petrovic said: "Despite the challenging economic climate, we delivered a strong performance in 2012.
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