The list was compiled by Allan Brodie, an author who specialises in the history of the British seaside. He said the grade II listed building was not given the accolade because it was "grand or pretty" but because it is the longest pier in the world with a train that takes visitors along the 1.34 mile stretch.
Mr Brodie added: "The pier was built in 1889 by James Brunlees and it was adapted to carry an electric tramway in 1890. It has subsequently been added to and rebuilt following a number of fires. These progressive alterations add to its interest.
“’The other contenders for the pier category were Weston-Super-Mare and Clevedon, but I have always felt an affinity for Southend. It’s not the prettiest or the grandest of piers, but what’s remarkable is that it is over a mile long, and you can actually get a train from one end to the other.”
The other "seaside wonders" were the scenic railway at Dreamland in Margate, Blackpool Tower, The Grand Hotel in Scarborough, the Hippodrome at Great Yarmouth, Brighton Lido, and the Royal Pavilion in Brighton.