Migrant workers are at an increased risk of exploitation on construction sites, a new report has warned.
The probe by Achilles, which deals in supply chain risk, found migrant workers are vulnerable to unexplained deductions from wages, restricted access to mobile phones and “informal or unclear” employment arrangements.
Based on interviews at hundreds of sites across the country, it found that the complexity of supply chains exacerbates the vulnerability of workers, especially those whose grasp of English is limited or whose immigration status is uncertain.
According to data collected under Achilles’ ethical-business programme, almost a third of the 9,834 workers questioned had had their employment arrangements communicated informally, such as verbally or by text. The practice is particularly common in the drylining and fit-out sectors, it suggested.
Investigators spoke to 111 workers who said deductions to their wages post-employment had not been explained to them and were in addition to taxes they had expected to pay.
A further 21 workers reported that they had been required to pay some kind of recruitment fee prior to their employment.
Ten workers said they had not been paid directly into their bank account, while three said they had been restricted from accessing or using their own mobile phone.
According to the report, although the number of cases was low, they gave an indication of the issues facing migrant workers, particularly those who do not speak fluent English.
“Several of the interviews that identified issues outlined above involved migrant workers with mixed levels of English language ability,” it said.
“Their immigration status, limited language ability and awareness of UK employment law presents a greater cause for concern, given the likelihood that these individuals may not be aware that they are being exploited.
“Individuals may also not be aware of the employment rights afforded to them under UK law.”
Much of the interview data did not directly indicate the prevalence of modern slavery, it said.
“However, several of the issues, combined with a complicated supply chain structure which is supported by a migrant workforce, present the possibility that individuals may find themselves subject to exploitation,” the report added.
The research, which was carried out between 2021 and 2024, was supported by major contractors including Balfour Beatty, Kier, Morgan Sindall, Sir Robert McAlpine and Wates.
The UK’s former independent anti-slavery commissioner, Dame Sara Thornton, who is now a consultant for UK asset manager CCLA which looks after investments for charities, said the report highlights that the sector must do more to tackle the issue.
“As investors, we have been concerned for some years about the risk of forced labour in construction and we have used our influence to raise awareness and encourage effective responses,” she said.
“This latest report identifies several key issues which suggest that forced labour may be present – the sector must do more to reduce the risk to their businesses and vulnerable workers.”
Joanne Hennessy, partner and head of business immigration at law firm TLT, said the report highlighted the high risk of modern slavery in the construction sector, driven by ongoing challenges such as labour and skill shortages.
“The data is worrying. However, there are steps contractors can take under the Modern Slavery Act to mitigate risks,” she said.
“Conducting right-to-work checks, ensuring visibility on supply chain processes and taking steps to contract responsibly are sensible and essential steps that will help combat modern slavery.
“Being alive to the issue and taking a proactive interest in the supply chain will go a long way to narrowing opportunities for workers to be exploited.”