Despite the promises of government ministers the new Universal Credit system does not always pay.
The scheme joins up six working age benefits and tax credits with the aim of making it easier to take work and to make sure it leaves 'strivers' with more money at the end of the month.
But anti-poverty group the Joseph Rowntree Foundation (JRF) has found that some will be left out of pocket when the changes come in, and that many will be left with too little income to be able to live a basic life.
Universal Credit gives more to those adults with children that move into work of up to ten hours, but after that the amount of benefits tails off, meaning it doesn't pay to increase hours past this point.
Full-time work can end up paying less than part-time work for families with children.
The report says that "for lone parents and second earners on the minimum wage, working 30 or more hours a week will reduce disposable income compared with working fewer hours".
Increased childcare costs and lower benefits are to blame for cutting the income full time workers will have left after they pay basic household bills.
Most lone parents and second earners are women, and Universal Credit penalises them even if they want to work more, adding this to the recent government changes, including tax credit cuts and pension age rises, that punish women.
JRF says that benefit "cuts before and after UC's introduction will leave many families significantly worse off overall".
Under the scheme single people will only receive 40% of the amount they need to live a basic life, and couples with children only 60%, so more poverty is guaranteed when it is introduced.
Universal Credit was slated for a UK-wide introduction in October this year, but computer problems announced this week mean only ten jobcentres will be using it fully by then.
Lord Freud, the government's welfare minister, wrote this week that "Universal Credit will allow people to see that a move into work or increasing their hours at work will be simple and financially worthwhile."
The latest figures prove that it won't be worthwhile for everyone.