Hallam adjoins the Princes Highway, 5 km east of Dandenong and 36 km south-east of central Melbourne. By the 1850s, selectors had taken up land in the area, grazing cattle and horses and milling the red gum timber.
William Hallam came to the district in 1856, later taking over the post office and operating a store and hotel on the corner of the Gippsland Road where the present Hallam hotel stands. This became a meeting place for drovers and farms and the locality became known as Hallam's Road. When a station was established in 1880 on the railway line from Melbourne to Gippsland just to the south, it also took the name. However, a settlement did not develop around the station as in most other places. The station stagnated, closed in the 1970s, but later re-opened.
There was a school in the area from 1858, occupying several different locations. It moved to a site on Hallam's Road in 1904. In 1923, its name was shortened to Hallam, as was the post office's. Hallam received a brief mention in the Victorian municipal directory of 1930:
In the 1950s, the growth in industry and housing at Dandenong led to some growth at Hallam. A larger school was built north of the Princes Highway in 1963, followed by Hallam high school in 1971.
Until the 1960s, dairying was the main agricultural pursuit. Residential development began in the north-west of Hallam. By the end of the 1980s housing subdivisions were in the north-east and south-east of Hallam, and the south-west part was home to industry. The shops at Spring Square were built. Hallam's sole mainstream (Uniting) church was acquired by the Russian Orthodox church, and Coptic and New Apostolic churches later opened.
Hallam's northern boundary is the Eumemmerring Creek and the Monash Freeway. The creek has a linear park with bike trails and the freeway has sound barriers. The central west-east axis is the Princes Highway and the southern boundary is closely paralleled by the Gippsland railway. Before the freeway, known as the Hallam Bypass (2003), Gippsland motor traffic was funnelled through Hallam and left to anxiously await a right turn into the South Gippsland Highway, Hallam's west boundary. The modern traffic conditions are a far cry from the Hallam pub with the surrounding farms.
Hallam senior secondary college had 942 pupils in 2014 and Hallam primary school had 424 pupils.
The residential sector east of Hallam Road has neither school nor shops, but a few kilometres down the Princes Highway there is the Fountain Gate shopping centre and schools.
Hallam's census populations have been:
Berwick-Pakenham Historical Society, In the wake of the pack tracks: a history of the Shire of Berwick, now the City of Berwick and the Shire of Pakenham, 1982
Deborah Stephan, Hallam 1830-1930, City of Berwick, 1993
J. Wells, Berwick: some aspects, 1980
J. Wells, More colourful tales of old Gippsland, 1980