The chief financial watchdog has been examining hundreds of pension transfer transactions amid fears that retirement savers could be bearing high costs for switching into self-invested schemes whose flexibility they won’t use.

Experts say that with sales commissions as high as 5 per cent on offer to financial advisers and the risk of losing valuable benefits such as double-figure guaranteed annuity rates on certain types of existing plans, some investors may have been poorly advised to transfer into self-invested personal pensions (Sipps).