Childcare perks are also completely lost once either parent earns £100,000 or more.
Michael Healy, of IG, said: “The £100,000 threshold is becoming increasingly detached from reality. It has been frozen since 2010, a time when Gordon Brown was our prime minister and Gary Neville still played for Manchester United.
“Wages and inflation have risen sharply since that distant time, meaning millions more people have been dragged into a tax trap, or otherwise stunting their career development to avoid it.”
The analysis comes ahead of Prime Minister Andy Burnham’s first Budget in October, when the Government is widely expected to raise new taxes.
Personal tax thresholds will remain unchanged until at least April 2031, after former chancellor Rachel Reeves extended the freeze for a further three years at her last Budget.
The additional annual tax revenue from not uprating the £100,000 threshold is estimated to reach £7bn a year by 2031, figures from IG show.
Had the threshold risen with inflation, earners today would only start to lose their personal allowance at around £160,000. An inflation-linked threshold would probably be worth around £174,000 by 2031.
