Unite has lost more than 700,000 members since it was formed, analysis by HuffPost UK has found.
The trade union has seen the departure of 705,797 members over a 13-year period — raising questions about its long-term strategy.
Unite was formed when the Transport and General Workers’ Union merged with Amicus in 2007, making it the UK’s largest trade union.
That year, the newly-formed union boasted 1.95 million members — but that figure had dropped to 1.24 million by 2020, the most recent year for which data is available.
Unite’s membership slump meant it was overtaken by Unison as the UK’s largest union in 2018.
A Labour source suggested Unite’s preoccupation with the internal workings of the party when Len McCluskey was general secretary, rather than resolving workplace disputes, was partly to blame for the exodus of members.
Under McCluskey’s decade-long tenure, more than 260,000 members quit Unite.
McCluskey stood down from the role last year and was replaced by Sharon Graham.
“Len McCluskey’s pathological obsession with the Labour party has seen Unite drop from first to second biggest union in the country,” one Labour insider told HuffPost UK.
“Unite and other unions haven’t taken membership engagement or retention seriously for a generation. Rather than invest and modernise they merge.
“They’ve failed to deliver for members on bread and butter issues like pay and pensions, unlike Unison and the National Education Union (NEU), that beat Boris Johnson and won on school safety and gained members as a result.
“Instead, Unite members constantly saw Len on TV banging on about Jeremy Corbyn like he was Jesus Christ himself. They cancelled their direct debits as fast as they could — a left wing demagogue isn’t going to put meals on the plates of their children.”
However, one trade union source disputed that Unite’s membership drop was due to McCluskey’s involvement in politics and suggested changes in the nature of work, such as the rise of the gig economy and the covid pandemic, were a factor.
“Len McCluskey won three general secretary elections,” they said.
“He did get involved in politics, but 99 per cent of his time was on industrial issues.
“There is a wider decline in union membership that is to do with unions being stripped of a lot of their power, so fewer people think there is any point in joining.
“It all goes back to Margaret Thatcher and the miners’ strike.”
Since taking on the top job in August last year, Graham has made it her mission to distance herself from the McCluskey years, vowing to focus on members and the workplace rather than internal Labour party battles.
Her campaign slogan for the general secretary role was “back to the workplace”.
According to a source, Graham has recently hired a new data analyst to drive membership engagement as well as economists and forensic accountants to investigate employers.
Sources close to Graham say she inherited an “unholy mess” from McCluskey over the £70m loss arising from its controversial Birmingham hotel complex, as well as a new pensions headache.
Unite spent £100m on the Birmingham project, but two independent valuations have put its value at less than £30m, prompting Graham to order a QC-led inquiry.
The union also has to plug a multi-million pound pensions black hole, which has prompted fears it could be forced to abandon its final salary scheme in favour of a less generous package — something Graham opposes.
One union source said: “The pensions situation is another example of Sharon having to clear up the mess she inherited from her predecessor.”
The general secretary also insisted there would be no “blank cheque” for Labour, which currently receives £1m from Unite as an affiliation fee plus hundreds of thousands of pounds in political donations.
In February, Graham threatened to pull funding from the party over the Coventry bin dispute, where lorry drivers in the Labour-run city have been in a stand-off with the council over pay.
“Sharon was elected on a platform of rebuilding workplace structures and avoiding politics,” the Labour source said.
“Members wanted a change and they wanted their union back.
“That remains her focus and where she intends to put resources, rather than Labour.
“Sharon took on Labour in Coventry because she was elected on this platform and has to deliver for her base and show Unite has had a systemic and overwhelming shake-up.
“If Unite doesn’t change they will continue to lose members and this is what keeps Sharon awake at night.”
For many of the UK’s top unions, the story has been one of decline. The GMB union has also seen a steady decline in members over recent years.
Some however, have managed to buck the trend.
In 2020, Unison increased its membership to 1.4 million in 2020, up from 1.37 million in 2019 and 1.36 million the year before.
Meanwhile, the NEU, Britain’s biggest teaching union, saw a membership surge of more than 50,000 during the coronavirus pandemic.
Unite sources said the union had attracted 20,000 new members in January and February.
A Unite spokesperson said: “It has been just over six months since Sharon took office and in that time she has changed the way we count our members — to get a more accurate picture of our paying membership, power areas and new areas.
“This makes it more complicated to do comparisons but we can absolutely confirm that in recent months the number of new joiners have been up considerably compared with the same month last year. Many of these are also from new areas of the economy.”
Unite’s membership woes in numbers
2007 - 1,952,226
2008 - 1,635,483
2009 - 1, 572, 995
2010 - 1, 515, 206
2011- 1,510,026
2012 - 1,424,303
2013 - 1,405,071
2014 - 1, 405, 838
2015 - 1,382,126
2016 - 1, 282, 671
2017 - 1,310, 508
2018 - 1, 291,017
2019 - 1,277,491
2020 - 1,246,429