UK - Pension scheme liabilities could hit £1.2trn (US$1.7bn) by the end of December as a result of a sharp decrease in AA corporate bond yields, Xafinity Consulting warned.
The projected figure would equate to a 45% rise from £823bn in January this year.
The consultant said a decrease in corporate bond yields - from 6.7% in January to 5.5% at the end of the year - meant scheme accounting liabilities would reach £1.2trn by the end of the year.
It also warned bond yields were likely to continue to plummet, making the situation worse for scheme managers.
Xafinity Consulting director of corporate solutions Robert Hunt admitted liabilities were "winning" despite the rally in asset prices.
He said: "Liabilities rises continue to out strip gains in asset markets over the year. The introduction of additional allowances for future mortality improvements could see liabilities increase by a further 8%.
"Add in the gearing effect and you could see a very significant increase in the deficit disclosed in year end accounts."
He called on scheme managers to adopt a more tailored approach to the issue of longevity.
"Opinions on longevity are mixed; on the one hand doctors are saying that our children are going to live to 100 at the same time as reporting obesity problems. Therefore, it's essential those involved in funding and running schemes agree longevity assumptions that are appropriate for their scheme.
"Such investigations should cover all the variables that affect life expectancy like lifestyle, occupation, location and historical data."