Benjamin Francis Conn Costelloe (c.1854-22 December 1899) was a barrister and Liberal Party politician.
Costelloe made three unsuccesful attempts to win a parliamentary seat: at Edinburgh East in the 1885 general election, at North Wiltshire at the 1886 general election and at St Pancras East at a byelection in July 1889.
In 1889 he was elected to the London County Council as a Progressive Party councillor representing Tower Hamlets (Stepney). From 1892-1898 he was a councilor for Chelsea, and in 1898 was elected to represent Bethnal Green South West.
In 1897 he was elected to the London School Board to represent the Tower Hamlets Division.
He died in December 1899, aged 44, following an operation to remove a growth from his brain.
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- ↑ "Death of Mr. Costelloe. A Well-Known County Councillor". Pall Mall Gazette. 22 December 1899.