Dr David Wrigley, a GP and deputy chair at the British Medical Association, said the impact of the tax rise would be “monumental”.

He said on X that many were “already on a financial tight rope” and called for a “rapid announcement of full reimbursement”.

Paul Stanley, a manager at a small GP surgery in Northumberland, said a practice of his size would see a bill of more than £40,000 a year after the tax increase.

He told BBC Radio 4’s Today programme that the “unfunded increase” in staffing costs could “ultimately impact on our resources and staffing levels”.

Shropshire GP Dr Jess Harvey echoed Mr Stanley’s concerns.

“Unless we’re being given suitable remuneration to cover this National Insurance inflation, we’re going to really struggle,” she said.

“If we don’t get enough money to continue to run these practices, then we’re not going to be able to provide the service that people want.”

Mike Padgham, chair of the Independent Care Group, which represents social care providers, said the sector had been “left out in the cold”.

“We now employ collectively, more than the NHS – 1.7 million people. So those extra charges are going to hit charities and private sector providers alike when we’ve been squeezed by local authorities who are themselves short of cash.

“So if we pay more, we’ll have to charge more.”

Geoff Butcher, the owner of a company which runs six care homes, said the tax increase will cost £200,000 a year, representing 50% of his firm’s free cash.

He told the Today programme he fears he will “almost certainly” have to pause planned renovations in light of the increased contributions.

“I think it will exacerbate the speed of closure of homes,” he said.

Hospices UK said those providing NHS services should be treated the same as NHS bodies.

“Paying brilliant, compassionate hospice staff a fair salary makes up the biggest proportion of running costs, and so it’s disappointing the chancellor didn’t exempt charities, or providers of NHS services which aren’t formally part of the NHS, from yesterday’s National Insurance rise,” it said.