Perason worked as a chainworker at the Brown, Lennox and Co. at Pontypridd, where his father had also worked, from 1913 until 1938. In 1920, he was elected treasurer of the local branch of the Chainworkers Associatio, and in 1934 was ruuner-up in the ballot for the position of national secretary of the association. During the First World War, he served with the Welsh Guards from 1916 until 1919. In 1924 he was elected secretary of the Pontypridd UDC Labour group even before his election as a member of the council.
Pearson was a member of the Pontypridd Urban District Council from 1926 until 1938, representing the Trallwn ward. He served as chairman in 1937-38. In 1928,he was elected as a member of Glamorgan County Council for the Cilfynydd ward, defeating long-serving Liberal Alderman William Roberts Davies, who had been a member since 1898. He remained a member until 1945. In 1933-34 he was chairman of the Pontypridd Education Committee, and he became a JP in 1939.
Following the death of the Member of Parliament (MP) for Pontypridd, David Lewis Davies in 1937, Pearson was selected as the new Labour candidate, narrowly defeating local miners' agent W.H. May at a selection meeting at Pontyclun on 15 January 1938. Following his victory at the 1938 by-election, and served until his retirement at the 1970 general election. He was a government whip as Comptroller of the Household from 1945 to 1946, and Treasurer of the Household from 1946 until 1951. He was appointed CBE in the 1980 Birthday Honours.
Arthur Pearson was unmarried.
- Jones, John Graham. "Arthur Pearson(1897-1980)". Dictionary of Welsh Biography. National Library of Wales. Retrieved 19 June 2021.
- Jones, John Graham. "Arthur Pearson (1897-1980)". Dictionary of Welsh Biography. National Library of Wales. Retrieved 19 June 2021.
- Leigh Rayment's Historical List of MPs
- Hansard 1803–2005: contributions in Parliament by Arthur Pearson
| Comptroller of the Household
| Treasurer of the Household
|Parliament of the United Kingdom|
David Lewis Davies
| Member of Parliament for Pontypridd
1938 – 1970