The city was founded sometime in 800 AD, though there is plenty of evidence that suggests that the area was inhabited since 500 BC. The present day area of Niranam and Kadapra on the western part of Thiruvalla was submerged under the sea before that. The name Tiruvalla is a colloquial form of Shiruvallabhapuram which is the Malayalam version of the earlier coinage Srivallabhapuram, named after the chief deity of the central temple complex, Sri Vallabhan. It is interesting to note that the ancient name of Thiruvalla was "Valla vai". This name had some relation with the river Manimala which was known as "Vallapuzha". The mouth is known as "Valla vai". On the western part of Thiruvalla, the rivers Pampa, Manimala and Achen Kovil join for a panoramic view.

As in many other places in India, the culture and heritage of Thiruvalla are tied up with the temples. Historical evidence such as copper plates and proclamations point to Tiruvalla as a flourishing and major center of spiritual and educational prominence in AD 1100. The Sree Vallaba Temple governed a Vedic School with one thousand students and one hundred teachers. The temple also maintained a hospital in the service of the public at large. The rulers of Thiruvalla belonged to the Thekkumkoor Dynasty, which had one of its headquarters at Edathil near Kavil Temple. Today's Paliakara Palace is a branch of Lakshmipuram Palace of Changanacherry which was the branch of Alikottu Kovilakam of Pazhancherry in Malabar. Similarly, Nedumpuram Palace is a branch of Mavelikkara Palace is an heir to the Kolathiri tradition of Udayamangalam.

Christianity arrived in Tiruvalla early through St.Thomas who is believed to have come to Niranam in A.D. 52 through Purakkadu. Tiruvalla Christians were part of the autonomous Church in the unity of the Catholic Church, until the seventeenth century when due to the intervention of the Portuguese fathers a schism occurred leading to the formation of Jacobites under the Patriarch of Antioch. On September 20, 1930, the Reunion Movement took shape when the two Jacobite Prelates, the late Archbishop Mar Ivanios and the late Bishop Mar Theophilos, joined hands leading to the establishment of Archdiocese of Trivandrum and the Diocese of Tiruvalla, by Pope Pius XI.

Tiruvalla was never under direct rule and before India's independence from the British rule in 1947 it was governed by the Travancore dynasty. The Tiruvalla municipality started functioning in 1919, with Shri. M.K. Kesavan Nair as the first Chairman of the Municipal council. The constitution was officially approved on October 8, 1920. The municipal office has established several public health facilities, libraries and sports facilities.