DESCRIPTION:
A post office was opened at the goldfield settlement of Riverdale on 1 July 1896. As a Riversdale already existed in Southland it was necessary to use a new name, so the surnames of two settlers, Messrs Bain and Graham, were compounded to produce the name Bainham. A telegraph office was established at Bainham on 8 September 1898 and John Bain was appointed postmaster and telephonist.

Edward Bates Langford became postmaster in 1923. From 1925 there was talk of erecting a new post office building to the plan of Okaramio Post office but in January 1928 Langford suggested that if he built a new building to combine a general store, the Post Office Department could lease part of it from him as a post office. The Post Office Department agreed and an annual rent was decided on.

It is not known who designed the building but it was built by two locals that year. About 1928 the earlier post office building was moved from across the road to its present site behind Bainham Store.

Miss Lorna Langford began working for her grandfather in 1947 when she was still at school. She became postmistress in 1952 and took over the general store in 1954, owning and operating the agency of New Zealand Post Ltd and the general store until 2008, before passing the torch to Sukhita Langford.