Retirees can expect their regular income to fall by 40%, according to research by annuity provider Partnership.
Its analysis of HM Revenue and Customs (HMRC) data also revealed the regions where retirees are most likely to see their income drop, with London (-48%), the east of England (-40%) and the south east (-40%) topping the list.
On a county basis, those in Buckinghamshire (-45%), Cambridgeshire (-44%), Leicestershire (-42%) and Hertfordshire (-42%) are the most likely to see a significant reduction in their income when they retire.
Andrew Megson (pictured), managing director of retirement at Partnership, said: “While people in retirement are likely to have fewer outgoings, it is still hard to imagine that anyone would not feel the pinch if they lost a third of their income overnight.
“Even if their pension is topped up by income from savings and investments or part-time work, it is still likely to be quite a shock.”