It was until 1937 when a new 2-storey public health building was constructed opposite the immigration office and was completed in 1938. Its first floor was the municipal office while the second was the public health center.

Later in the administration of mayor Piti Chawapong, with the growth of population and economy, Hatyai Subdistrict Municipality was promoted to be Hatyai Municipality on 16 March 1949 with its subsequent growth. Then, on 10 May 1961, the municipality area was expanded to 8 sq. km.

•  Due to its growing municipal officers and public services, mayor Komes Intawong and his municipal councilors proposed and constructed a new municipal office building at 445 Petchakasem Road, Hatyai, Songkhla with a 5 million baht loan for a land purchase and a 4,864,000 baht municipal budget for the construction cost and it was completed on 22 March 1968.

The building was officially open on 13 August 1968. Since then, the municipality development has continued greatly. The second municipal area expansion was undertaken from 8 sq. km. to 21 sq. km. on 24 April 1977. It was in 1995 during the administration of mayor Khreng Suwannawong when the municipality was promoted to be Hatyai Municipality with its growing revenue and population.

•  Currently, with its population of 157, 316, Hatyai Municipality covers 21 sq. km. bordering Klong Hae Subdistrict on the north, Khor Hong Subdistrict on the south and the east, and Khuan Lang Subdistrict on the west. The municipal development has been witnessed since its first stage and its growth will be continuing with its high potentialities.