The Pension Protection Fund (PPF) has said in its latest monthly 7800 Index that the aggregate deficit of the 5,588 schemes included is estimated to have decreased over the month to £85.6bn at the end of June 2018, down from £94bn at the same point in May.
It said the funding level increased from 94.5% to 94.9% over the month.
Total assets were £1,611.2bn and total liabilities £1,705.2bn, while there were 3,633 schemes in deficit and 1,955 in surplus.
Boris Mikhailov, investment strategist, global investment solutions at Aviva Investors, said: "Despite a slight deterioration in the reported PPF figures today, the aggregate funding position of pension schemes still stands at 94.9%.
"This compares to 89% funding position a year ago and 78% as at the of June 2016. Over longer periods, however, if you rewind back to 2011, the funding levels reached dizzy highs of well over 100% funded."
Mikhailov said that while schemes had adopted de-risking strategies to take advantage of improvements in funding positions, more could be done to increase the certainty of meeting pension promises.
He noted the 2018 Mercer European Asset Allocation Survey said only 34% of UK pension schemes had formal de-risking triggers in place, with others taking an informal approach.
"This means that opportunities to 'bank' unexpected improvements in funding positions by taking the risk off the table could be missed," he warned.
"With volatility across financial markets only likely to increase this year, pension schemes need to brace themselves for an even choppier ride. Without a clear game-plan, most schemes will be none the wiser if markets start moving against them."