Complex rules around inheritance tax (IHT) must be “simplified” in order to close the gap, according to law firm Collyer Bristow, after new statistics published by HMRC show that the IHT gap has grown to £600 million in 2016/17, rising 50 percent from £400 million five years ago in 2012/13.

Total IHT take jumped 13 percent to a record high of £5.3 billion last year, up from £4.7 billion in 2016/17.

James Badcock, partner at the law firm, said: “The fundamental problem is that IHT is now so complicated that innocent taxpayers are making honest mistakes and underpaying tax.

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