Haslam was born in Bolton, Lancashire, and was a member of the choir and Sunday school at the Wesleyan Methodist church on Bradshawgate.
He and his brother James Cyrus Haslam[1] joined the firm of Donaldson, Andrews, and Sharland, working as a warehouseman and traveller, until setting up in business for himself in Jamestown.
He disposed of his business and moved to the city around 1885, living at "Woodlands" then "Heywood", both in Unley Park and working for Globe Timber Mills, the company founded by his brother-in-law Simon Harvey (1843–23 September 1927), and in which he had a considerable interest.
Haslam married Annie Jenkyns Roach (c.1851 – 16 February 1929) of Penwortham on 24 June 1873; they had three daughters (Mabel, Olive and Daisy) and four sons (Albert, William Osborne, Leslie and Spencer).
Haslam, a fishing village on the West Coast of South Australia, 45 km north-west of Streaky Bay was named for him in 1893.