The amount was disclosed by police forces in response to Freedom of Information requests made by PA news agency.
The Metropolitan Police said it has spent £4 million policing the climate group’s protests which took place between 13 September and 20 November.
Transport Secretary Grant Shapps said he was “appalled” by the figure.
Mr Shapps told PA: “I am appalled at the amount of time and public money that’s been spent policing the selfish actions of Insulate Britain.
“Not only did their guerrilla tactics wreak havoc on our roads and inflict misery to thousands of motorists, but they diverted our emergency services away from vital work, costing the UK taxpayer millions in the process.”
Of the £4.3 million, £3.1 million was spent on the cost of 6,651 officers and staff.
£600,000 was spent on deploying vehicles, and an overtime cost of £300,000 was racked up.
Four other forces disclosed figures totalling more than £300,000, but this only included overtime bills, and so the cost of policing protests in their areas was much higher.
They were Hertfordshire Constabulary (£185,000), Surrey Police (£110,000), City of London Police (£44,000) and Greater Manchester Police (£10,000).
Insulate Britain’s core aim is for the Government to insulate all UK homes by 2030, to cut carbon emissions.
Their protest methods primarily consist of blocking roads, causing long traffic jams. Activists often glue their hands to the road or to each other to make it harder to remove them.
The group frequently targeted the M25, the UK’s busiest motorway, but also blocked roads in Manchester, Birmingham, London and the Port of Dover, Kent.
At one stage police officers were deployed at every junction of the M25 in an attempt to stop the group.
The group are often met with frustration from the public. Earlier this month, a woman who allegedly nudged an Insulate Britain activist with her SUV was charged with assault.
Ken Marsh, chairman of the Metropolitan Police Federation, described the cost of policing the protests as “staggering”.
He said: “Unfortunately we have to police what’s put in front of us.
“It’s disgusting that we’re having to spend that sort of money on these protests.”
Ten Insulate Britain supporters have been jailed for breaching the injunctions so far, with prison sentences ranging from two to six months.
Mr Shapps said: “We will continue to act against this lawless behaviour while the Government gets on with tackling climate change.”
Insulate Britain spokeswoman Tracey Mallaghan said the climate group would “much rather money was being spent on insulating homes and helping get people out of fuel poverty”.
She also pointed out that their actions have made home insulation “something people are talking about.”
In response to questions on their decision to block roads, she said: “When we went to Parliament as Insulate Britain, that just didn’t get the same amount of (media) coverage.
“It seems the only way we can get air time is by annoying enough ordinary people.”
She added: “I just can’t look my children in the face and say ‘this problem is too big, we’re not going to do anything’.
“Our Government has proved time and time again they’re not doing what is necessary for our children, for the future. So how can we stop?”