Hospitals and clinics in the UK are increasingly finding themselves garnering attention from a wealth of private healthcare investors in the US eager to capitalise on the opportunities being created by an increase in NHS outsourcing.

Whilst the UK has long been on the radar of many US investors, with Hospital Corporation of America (HCA) present here since 2006, the number of Stateside companies hoping to build relationships with the NHS is growing apace.

Over the last 12 to 18 months US companies Acadia Healthcare, Universal Health Services (UHS) and Tenet Healthcare all entered the UK market for the first time and industry analysts predict more will follow, whether through direct partnerships or acquisition.

Commenting on their move into the UK market Tenet Healthcare said that “privatisation of UK marketplace, given market inefficiencies and pressures on the National Health Service, should create organic and de novo opportunities”.

The company currently employs more than 130,000 in the US and operates 470 outpatient centres and 84 acute care and 20 short stay hospitals. Its successful acquisition of Aspen Healthcare in 2015, which operates private hospitals and clinics in the UK, is being seen as “increasing opportunities to work with and support the National Health Service”.

This is just one of a handful of large-scale inward investment moves. The number of takeovers of mental healthcare providers alone rose from 16 in 2014 to 22 in 2015 – the result of which has left the UK’s £16bn mental healthcare market bracing itself for a wave of consolidation.

Indeed, in 2014 UHS acquired Cygnet Healthcare, the addictions specialist, for £205m and last year Acadia’s £1.33bn acquisition of Priory Group was the headline deal – one that Vernon Baxter, chief executive of HealthInvestor, described as “a real statement” signalling strong investor interest in the sector. The £1.33bn price tag represented more than 10 times EBITDA.

Both UHS and Acadia have made clear their expansion ambitions. Cygnet/UHS purchased Alpha Hospitals last year, while Acadia/PIC bought the private equity firm Care UK’s mental health division.

Speaking to the Financial Times, Justin Crowther, head of healthcare at Catalyst corporate finance, said that the sector should expect a “wave of deals” over the next 12 months as several private equity owned specialist care organisations come up for sale. He said: “The presence of some very well capitalised strategic acquirers presents a healthy exit environment for these owners”.

What has prompted the surge in interest in the UK healthcare market? It is a combination of factors that the mental healthcare sector succinctly illustrates.

The BBC’s expose in 2011 of staff abusing and neglecting patients at Winterbourne View hospital for those with learning difficulties, then run by private equity owner Castlebeck, put private mental healthcare providers across the UK on close watch.

Since then, budget cuts to state-funded services has seen the number of in-house beds provided by the NHS for people treated for mental health or learning disabilities fall by 23% over the last five years, with those provided by the private sector growing by 8% over the same period, according to healthcare consultancy LaingBuisson.

Add an ageing population, increased diagnosis of mental healthcare issues, a growing trend towards specialisation and the fact that the UK private healthcare market remains relatively untapped compared to the “expensive and congested” (Weil, Gotshal & Manges) US market, it becomes clear to see why the UK is of significant interest to US investors.