The Salvation Army said over 12 months, 136 British nationals needed help from The Salvation Army's network of safe houses and outreach workers, making them the fifth most common nationality accessing the charity's support.
The Salvation Army's report, which includes evidence from the its referral officers, found that the rise in British victims was likely to be down to gangs trafficking drugs into rural areas, a practice known as "County Lines".
The Christian charity also said files revealed a worrying new trend called "cuckooing" where dealers take over a vulnerable person's home as a local base and manipulate them into working for them.
Of the 136 British modern slavery victims supported last year 96 were victims of forced labour, 30 were forced into sexual exploitation and nine were trapped in domestic servitude
Major Kathy Betteridge, The Salvation Army's Director of Anti Trafficking and Modern Slavery, told Premier people usually become victims because of their addictions.
"So whether it's an alcohol or drug addiction, that could have created them to become homeless and destitute, and therefore they are more susceptible to being a target," she said.
"In some cases, the criminals use the drugs as a means to coerce and to keep somebody in bondage.
"So for the women it can be that they are made to take drugs or alcohol just because they have to do some often horrendous sexual services. For men, if they do have an addiction, then their payment is drugs."
The report also showed a total of 2,251 people from 99 different nationalities accessed Salvation Army specialist services within a 12 month period. Of these 1,247 were women and 19 per cent of whom were pregnant or thought they were.
The Salvation Army offers grants to help slavery survivors get their life back. They have been made for childcare costs to enable people to access education and training, and household items including furniture.
To help the public recognise and report concerns about modern slavery, The Salvation Army is launching a temporary tattoo.
The tattoos take the form of a barcode with the slogan #WeAreNotForSale, in reference to how slavery treats people as little as a commodity.
The public can buy, wear and share the tattoos around Anti-Slavery Day (18 October). Profits will pay for additional support for modern slavery victims.
Listen to Premier's Cara Bentley speaking with Major Betteridge here:
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