In Cardiff on August 3 they embarked on their third members’ hustings (out of an official 12 set to take place) to decide which of the contenders will succeed Boris Johnson as Prime Minister.
Mr Sunak is under pressure to overhaul his campaign as polling suggests he is lagging behind his rival and was dealt a blow after Sajid Javid pledged his support to Ms Truss.
Attention now turns to Sky tonight in a televised debate in front of a live audience.
The first Tory leadership debate took take place on Friday, July 15 on Channel 4, followed by a second debate on Sunday, July 7 on ITV.
When are the Tory leadership debates on TV?
Two debates happened during the contest, hosted by Channel and ITV, with another one to be aired on the BBC on July 25.
Louisa Compton, Channel 4’s head of News Current Affairs, Specialist Factual and Sport said: “We’re thrilled that all five candidates have agreed to take part in Channel 4’s leadership debate and answer questions from voters around the UK.
“This debate will be essential viewing for those wanting to know more about our next prime minister and what she or he stand for.”
Michael Jermey, ITV’s director of News and Current Affairs said: "Television debates at important elections help voters engage with politics.
"ITV has been the home of some of the biggest political debates over the past decade. Sunday’s debate will be an important event as the country’s next prime minister is chosen."
Prime Minister Boris Johnson resignation from inside Downing Street
How to watch the Tory leadership debates and what TV channel are they on?
The first debate on Friday, July 15 was broadcasted on Channel 4 at 7.30pm.
Kemi Badenoch, Penny Mordaunt, Rishi Sunak, Liz Truss and Tom Tugendhat all took part in the 90-minute debate, hosted by Krishnan Guru-Murthy.
The second debate took place on Sunday, July 17 and was broadcasted on ITV at 7pm, with the same candidates.
The BBC’s debate, Our Next Prime Minister, will take place in front of an audience of between 80 to 100 people in Stoke-on-Trent and will air at 9pm on Monday, July 25, on BBC One. It will be presented by Sophie Raworth.
The Sky debate will take place on Thursday, August 4 at 8pm.
John Ryley, head of Sky News, commented: “There has never been a more important time to reinvigorate the trust of voters in the office of the prime minister.
“This live TV debate on Sky News gives the final two candidates a chance to reconnect with millions by debating the major issues facing Britain.”
Leadership election Hustings schedule
Ms Truss and Mr Sunak will also take to the road to participate in 12 hustings organised by the party across the UK.
The dates and venues are:
Leeds on July 28
Exeter on 1 August
Cardiff on 3 August
Eastbourne on 5 August
Darlington on 9 August
Cheltenham on 11 August
Perth on 16 August
Northern Ireland on 17 August
Manchester on 19 August
Birmingham on 23 August
Norwich on 25 August
London on 31 August