The average Isa fund holding is £26,265 according to HM Revenue & Customs data, and the total average annual saving for UK savers would be £43.60.
Stuart Dyer, Rplan.co.uk’s chief investment officer, said: “The industry should be moving much more quickly than it is towards switching off trail commission on investors’ funds.
“It is a complicated process, but that is no excuse - our research shows that failure to do so is costing investors a substantial amount of money.
“Investors should be contacting the platforms holding their assets to ask if trail commission is being switched off on their holdings and, if not, why not.”
Rplan.co.uk discontinued trail commission on its customers’ funds in September.
Adviser view
Sebastian van Mook, financial adviser at Shropshire-based Abacus Associates, said: “A decision has been made, and a date has beeb set for turning off trail, so why waste time and effort talking about it.
“A line has been drawn for everyone to work towards. The pace that people chose to get there is their prerogative, as long as they do it and get to the finishing line.”