Intelligence has been gathered from the transport, food, agriculture, construction, manufacturing industries — plus nail bars, car washes, shellfish gathering and cleaning; the findings are described as "horrific" by Kevin Hyland, the UK's Anti Slavery Commissioner.
Data reveals men from ethnic Roma communities are most likely involved in criminal activities, with the UK and France described as the main destination for trafficked Romanian children.
Victims from Vietnam have been linked to nail bars, shellfish gathering, cannabis cultivation and prostitution, meanwhile Romanian workers are linked to car washes and food processing.
The report, 'The Nature and Scale of Labour Exploitation Across All Sectors Within the United Kingdom' is published by the government's Gangmasters & Labour Abuse Authority.
"The sad reality is that the criminality that drives exploitation and slavery is quite close to home in the towns, cities and countryside in which we live and work," Roger Bannister, interim chief executive of GLAA said in a statement.
"The barbaric nature of modern slavery means it destroys the lives of its victims, which is why we introduced the world-leading Modern Slavery Act 2015 and increased the Gangmasters and Labour Abuse Authority funding by £2.6 million a year to tackle modern slavery and wider labour exploitation." Victoria Atkins, Minister for Crime, Safeguarding and Vulnerability said in a statement.
READ MORE: Nail Bar Gang Exposed for Exploiting Teenagers in UK
In contrast to data from the National Referral Mechanism (NRM) which suggests Vietnamese, British and Albanian were the most common nationalities exploited for work, the GLAA finds exploitation of Romanian workers is most frequently reported. Forced labor accounts for a third of all exploitation, the majority of victims are from Eastern Europe.
READ MORE: Family 'Devastated' After Man Lived & Died as Modern Slave in London
Social Media
Social media is being used to recruit people, victims arrive in the UK ready to work for a job that doesn't exist. "Social media, particularly Facebook, is being used for job advertising, with introductions being made between victim and exploiter using this method," the report says.
Victims are discovering websites promising people jobs without the need to speak English by typing in "work in England" but these jobs often don't exist and Skype, FaceTime and online messenger services are used as a platform to strike up relationships with potential victims and perpetrators.
READ MORE: Cyber Slavery Rises As Criminals Sink Deeper Online
Travel
Minibus and coach services provide routes from Lithuania, Romania and Bulgaria, often costing US$202 (£150) per person each way, the ticket paid by the exploiter, leaving the victim in debt before they even arrive, according to the report.
Intelligence gathered by the GLAA also reveals non EU nationals have been brought to the UK for no other reason but to use them for slave labor by exploiting immigration controls (including the Common Travel Area) and visa systems. Some may have paid smugglers money to get to the UK, unaware they would be forced to work as a slave once they arrived.
According to data from the European Migrant Smuggling Centre, 17,500 migrants were suspected of being smuggled into the UK in 2016.
READ MORE: Reality of Modern Slavery: 'Trafficked to Wash British Cars in Plain Sight'
Money
New banking systems have also been highlighted as a threat. "There are reports of workers being paid by 'E-Card' where funds are accessed via log-in details sent by email. There are known occasions where the email addresses are controlled by the exploiter." The report states.
A new banking system called "Pockit" has been highlighted by the GLAA for being used in this way.
The UK construction sector employs approximately three million people and is a high risk industry for labor exploitation. The supply chains in the industry make spotting exploitation extremely difficult. Workers live in caravans in conditions frequently described as inhumane, unsafe and overcrowded and receive as little as US$ 6 — 12 (£5 —£10) a day.