From next April a salary of £143,700 will attract a tax bill of £50,000.
Those on a salary in excess of £100,000 will receive no personal allowance. The first £37,400 of their pay will be taxed at 20%, so they will pay £7,480. Somebody on £143,700 will pay 40% on the remaining £106,300 of their pay. This equates to £42,520, making a total income tax bill of £50k.
In addition they will pay about £5,250 in NI contributions. This makes a total reduction rate of about 38.5%.