Lloyd's has swung to a £3.62bn profit for the year to end-December from a loss of £103m in 2005.
The return to the black was seen as the result of a benign hurricane season and high US property and catastrophe insurance prices.
The combined ratio for the London insurance and reinsurance market was 83.1%, up from 111.8% in 2005.
Richard Ward, Lloyd's chief executive, said: "2006 was an excellent year for Lloyd's and the market has performed well. During the year, we benefited from strong underlying conditions and an exceptionally low level of catastrophes."
However, he added that it would be 'unrealistic' to expect such a favourable claims climate this year.
