The combined deficit of defined benefit pension schemes increased by £40bn in August according to a Pension Protection Fund index.
The PPF 7800 index gives the funding position for the DB schemes that are potentially eligible for entry to the lifeboat fund.
It calculates this based on the premium due to an insurer to take on paying the PPF levels of compensation.
At the end of July the aggregate deficit of the 5,794 schemes in the index was £180.1bn but it rose to £220.4bn at the end of August.
At the end of August 2016, the deficit was £413.1bn.
Last month total scheme assets were £1.55trn and total liabilities were £1.77trn. Scheme assets increased by 1.9 per cent over the month and increased by 4.5 per cent over the year.
Scheme liabilities increased 4 per cent over the month and decreased by 6.6 per cent over the year.
There were 4,261 schemes in deficit and 1,533 schemes in surplus. The number of schemes in deficit increased by 105.
The funding ratio decreased from 89. per cent at the of July to 87.6 per cent at the end of August.