Bupa UK experienced a 5% increase in revenues and experienced growth across all UK business units for the first time in five years.
The insurer's full year financial results showed that during 2015 it had experienced growth as a number of large companies extended private medical insurance (PMI) coverage across their whole workforce.
This growth saw improved rates of customer retention, and growth in new business in the small and medium-sized enterprises (SME) and corporate segments.
However, Bupa said this was partially offset by the continued, but lower rates of, decline in the individual health insurance segment.
Meanwhile, the increase in Insurance Premium Tax (IPT) has reduced the affordability of health insurance, the insurer warned.
Bupa said it was working to stimulate reform in private healthcare, contain healthcare costs and improve affordability for customers.
The insurer also said of its elderly care business, public funding pressures in the UK mean that local authority fees for care services are often below the true cost of delivering care, which is then compounded by the impact of inflation on operating costs.
Bupa said: "We are supportive of the move to a National Living Wage for our people. This will however increase the cost of delivering care and we are making the case to the government that fees from local authorities will need to increase to cover this additional cost.
"We are increasingly taking a firmer line when negotiating contracts with local authorities to ensure that we recover the true cost of caring for our residents."
Richard Bowden, managing director of Bupa UK said: "Our priority in 2015 was meeting customers' changing needs and making private healthcare more affordable. We have successfully negotiated the lowest price increases from major hospital providers that we have had for the last five years which resulted in lower premium increases for our customers.
"This focus on containing premium increases also resulted in the best customer retention rates in a decade.
"However, the uptake of health insurance is actively discouraged by the current tax regime, which penalises UK customers who have chosen to take personal responsibility their own healthcare.
"Since the introduction of IPT, hundreds of thousands of individuals have dropped out of the market.
"The UK now has the third highest rate of tax on health insurance out of 28 countries. It is our view that private healthcare needs to be treated like life or critical illness insurance, making it zero-rated -consistent with the practice of many other European countries.
"We are continually working across the sector to stimulate reform and improve affordability for customers. But how the government currently chooses to classify health insurance hampers this."
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