The combined pension deficit of UK companies pushed past £500bn last month as asset values fell slightly and liabilities remained stable, according to Xafinity.
Scheme deficits are higher than a year ago despite £20bn being ploughed into pension funds by sponsoring employers, Mercer data shows.
ITV has seen it pensions deficit grow to £390m as falling corporate bond yields and a £65m premium on a longevity swap carried out last year pushed up the shortfall.
QinetiQ has agreed a funding plan with trustees to tackle its £75m pension deficit after a High Court ruling cleared the way for it to switch to Consumer Prices Index-linking.
BT's has agreed to make a £2bn pension scheme contribution this month to help plug its £4.1bn deficit.
The Pensions Regulator is to investigate Trinity Mirror after the publisher slashed payments to its scheme by £70m in a deal to pay off debts.
Balfour Beatty has slashed its pension deficit from £354m to £188m over the last year through a mixture of employer contributions, de-risking and changing actuarial assumptions.
British Polythene Industries has agreed to top up the contributions to its pensions scheme from an asset-backed funding partnership after its latest triennial valuation.
Communisis has set up an asset-backed contribution arrangement with its pension scheme after a raft of measures to cut its deficit were cancelled out by market movements.
National Express's defined benefit coach pension plan has moved into surplus after closing its scheme to future accrual.