Labour's proposed ban on conversion therapy practices could cost businesses and the public sector as much as £100 million over a decade, according to an official government report. The legislation, which aims to outlaw abusive attempts to change individuals' sexuality or gender identity, is projected to have a negative impact on private firms and public sector bodies due to the need for staff training.

The full financial impact, including costs to the police, courts, and prisons, has yet to be calculated. However, the Impact Assessment claims the law will bring a societal benefit of £783 million over 10 years, based on projected reductions in depression among transgender and gay individuals. Critics have questioned these figures, citing concerns that the ban could inadvertently criminalize parents for attempting to dissuade their children from transitioning.

Maya Forstater, Chief Executive of Sex Matters, called the projected economic benefit "pure fantasy" and stated that the bill's costs have been "grossly underestimated." She argued that significant expenses related to police and court time, social services, and potential child welfare interventions have not been accounted for.

Shadow Equalities Minister Joy Morrissey expressed concern that imposing additional costs through the legislation would be detrimental to businesses already facing economic challenges. The Impact Assessment acknowledges that the evidence base for conversion therapy is "relatively limited" and that incidents are not officially recorded, leading estimates of prevalence to rely on self-selected samples. The study used a survey commissioned by lobbying group Stonewall to estimate that 75,000 to 93,000 people annually in England and Wales are victims of conversion practices.

The report suggests that improving the quality of life for these individuals will lead to a "monetised benefit," estimating a 10-year net present value of £783 million. It also anticipates potential positive economic effects from reduced workplace sick leave.

Conversely, the report concedes that the "overall impact on businesses from these measures is likely to be negative." It forecasts one-off familiarization costs for organizations in the private education and healthcare sectors, as well as for religious groups and the LGBT+ voluntary sector. The introduction of the law is predicted to cost taxpayers £45.8 million for training across the police, Crown Prosecution Service, courts, NHS, education, and social services. A Victim Support Service is estimated to cost an additional £240,000 over three years. Further impacts on the wider justice system, including the Prison and Probation Service and Criminal Legal Aid, are still under assessment. One-off "familiarisation" costs for the private sector are forecast to reach £13.6 million. The table of total costs to business and the public sector over 10 years includes a high estimate of £103.3 million and a best estimate of £59.7 million.