The CSA has been trying to win over the critics of its operations
Child maintenance payments collected or arranged by the Child Support Agency (CSA) topped £1bn in the 12 months to March, according to official figures.
A National Statistics report shows that 749,300 children in the UK benefit from the payments, up from 683,300 at the same time last year.
Some 67% of those liable are paying up, but there are still millions of pounds in arrears to get from absent parents.
The CSA has been criticised in the past for its performance.
According to the report, the CSA collected or arranged £1.01bn in child maintenance in the 12 months to March, up from £898m in the year to March 2007.
Of this amount, some £126m was arrears, up from £91m the previous year.
"It is really good news that a record £1bn in child maintenance is now benefiting almost 750,000 children. Payments of child maintenance currently lift 100,000 children out of poverty," said Work and Pensions Secretary James Purnell.
CSA chief executive Stephen Geraghty said: "We are getting more money to more children since March 2005.
"The CSA will continue to pursue parents who evade their financial responsibilities. Our message to them is clear - act now or we will."
The figures show that cases are being cleared faster, with the backlog of new applications beating the government-imposed target. It stood at 110,600 cases in March, down from more than 200,000 two years ago.
The new Child Maintenance and Enforcement Commission will this year take over responsibility for ensuring absent parents pay what they owe.
Janet Allbeson of charity One Parent Families, said unpaid debts needed to be targeted with new arrears of £16m a month still emerging, and a total debt of nearly £4bn.
The CSA, established in 1993, faced prolonged criticism for not delivering.
Last July the Commons public accounts committee said reform of the agency was one of the "greatest public administration disasters of recent times".
Shadow Work and Pensions Secretary Chris Grayling said: "The government has promised great plans for reform but the families that have experienced problems in the last few years will remain sceptical."