After leaving school, Howarth's first job was working at Barry Bull's Toombul Music.[2] He worked at Sony Australia as a sales rep from 1993 to 2001.[4] In 2002, Howarth joined his family's pest control business, alongside his mother, father and wife.[2]
Whilst campaigning for the 2016 federal election, Howarth claimed the Coalition Government had put nearly $1.5 billion into infrastructure in Petrie over previous three years.[9] He was returned to government benches with a swing in his favour 1.12%.[10] During this parliament he advocated for increased funding for the National School Chaplaincy Programme.[11] He also played a key role in the leadership spill which removed Prime Minister Malcolm Turnbull from his position, in 2018.[12]
During the 2019 election, Howarth enjoyed a significant swing in his favour, in line with other Liberal National Party candidates in Queensland, increasing his margin to 8.4%.[13][14]
Returning to Canberra, Howarth was made Assistant Minister for Community Housing, Homelessness and Community Services. After speaking to ABC Radio National in his newly appointed role, Howarth came under fire for trying to "put a positive spin on [homelessness]."[15] Howarth claimed that levels of homelessness had been reduced, over a 15 year period, from 8,926 people in 2001 to 8,200 people in 2016 despite a 20% increase in the population. The claim was challenged by some, who compared the number of rough sleepers at 6,810 in 2011 (a rate of 3.2 people per 10,000 of population) and risen by 20% to 8,200 (a rate of 3.5 per 10,000) by 2016.[16][17] He was given the role of Assistant Minister for Youth and Employment Services later in that parliament, where he advocated for the Youth Jobs PaTH internship program.[18][19]
In the 2022 Australian federal election Howarth won despite a 3.96% swing against him.[20] However, as the coalition had lost power, Howarth joined the ranks of the opposition for the first time. He was appointed as the Shadow Minister for Defence Industry and the Shadow Minister for Defence Personnel by the new coalition leader, Peter Dutton.[21] In this role he has been critical of the government's lack of urgency in developing Australia's defence industry given that Australia faces a geostrategic environment that is 'precarious and dangerous.'[22]
Howarth married his wife, Louise, in 1999, and they have three sons.[2] He lives in Clontarf in Queensland.[25] Howarth owns an investment property in Mount Pleasant in Queensland.[25]