Rishi Sunak and Liz Truss have until the end of August to explain to around 160,000 Tory members why they should be prime minister.
The pair saw off competition from senior Tories including Chancellor Nadhim Zahawi and Transport Secretary Grant Shapps - as well as Trade Minister Penny Mordaunt, who has just been eliminated - in order to reach the contest's final two.
They'll tour the country and attend various hustings events where they will be grilled by Tory members still trying to make up their mind as to who they want their leader to be.
Here's what you need to know about the candidates and the rest of the race to become prime minister:
Key dates in the race:
The Sun and TalkTV will host a head-to-head debate between Rishi Sunak and Liz Truss on July 26.Conservative Central Office will organise a series of hustings events where the hopefuls will be grilled by Tory party members.
The first hustings will take place in Leeds next Thursday and hustings will be held across the country and in all four nations of the UK.
Hustings events are also to be streamed on the Conservative Party website.
Conservative Party members will their receive postal ballots by August 5, with the ballot shutting at 5pm on September 2.
The winner will be announced on September 5.
There are at least two televised scheduled debates and further events could be confirmed, however organisers will be concerned about the damage caused to the party by the previous debate.
The first TV debate will be hosted by BBC One on Monday at 9pm, presented by Sophie Raworth.
Sky News will also host a live debate between the final two candidates at 8pm on Thursday August 4.
What do the candidates stand for?
Here's a rundown of what Mr Sunak and Ms Truss have indicated about their stance on policy areas important to Tory members.
- Tax and spending
Rishi Sunak: The former chancellor has pitched himself as the fiscally conservative candidate and criticised his rivals' plans to raise borrowing to pay for tax cuts as "comforting fairy tales".
He has promised to "deliver tax cuts that drive growth", but to do so in a "way that's responsible" and only "after we've got a grip of inflation".
Liz Truss: The foreign secretary has pledged to "start cutting taxes from day one" with a new Budget and Spending Review that would reverse April's rise in National Insurance and next year's corporation tax hike from 19% to 25%.
Rishi Sunak: Supports the current government's controversial Rwanda asylum policy, saying it will stop "an illegal set of criminal gangs who were causing people to die in pursuit of coming here".
Liz Truss: Also supports the policy and said she has worked closely with the home secretary on it.
- Identity Politics
Rishi Sunak: Has criticised "trends to erase women via the use of clumsy, gender-neutral language".
He has pledged a "manifesto for women's right", including opposing biological men being allowed to compete against women in sport and guidance for schools on how they teach issues of sex and gender.
Liz Truss: Has previously shelved plans for an overhaul of gender recognition rules to make it easier for trans people to change their legal gender.
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- Brexit and Europe
Rishi Sunak: The Leave-voter has promised to scrap or reform all EU law or bureaucracy still on the statute book by the time of the next general election, and have initial recommendations on whether each law stays or goes within 100 days.
Liz Truss: Voted Remain but has since embraced Brexit and scooped up the backing of staunch Brexiteers. Helped push through the Northern Ireland Protocol Bill which critics say breaks international law.
- Climate Change and Net Zero
Rishi Sunak: Committed to reaching net zero emissions by 2050.
He has pledged to keep the ban on building new onshore wind farms, but wants to introduce a legal target to make Britain energy self-sufficient by 2045 by overseeing a massive expansion in offshore turbines.
Liz Truss: Backs the net zero push, but would pause green levies on domestic energy bills, which could damage the target.
She says there is a strong case for lifting the ban on fracking and wants to move away from the EU's habitat directive in favour of a stronger British biodiversity target.
Rishi Sunak: Views the Nato target of 2% of GDP as a "floor and not a ceiling" and notes it is set to rise to 2.5% "over time" but refuses to set "arbitrary targets".
Liz Truss: Has pledged to increase defence spending to 3% of GDP by 2030 and strengthen the intelligence services. She said the government's current plan to cut the size of the Army to 72,500 in 2025 is "up for review".