A march in protest at government cuts passes parliament in London on its way to Hyde Park. Photograph: Peter Macdiarmid/Getty Images
This list of 42 benefit changes, compiled by the the charity Child Poverty Action Group (CPAG), gives a clear sense of the vast scale and complexity of the Coalition's welfare reform programme, which is aimed at saving £18bn a year from the social security budget by 2015.
The government's reform of welfare started in 2010. But the six come into effect on or after 1 April include some of the biggest and most high profile cuts, such as the Bedroom Tax, the household welfare cap, and the abolition of council tax benefit.
These new reforms will take £2.3bn a year out of the pockets of some of Britain's poorest households in 2013-14 alone. According to CPAG:
The £2.3 billion figure represents how much is cut from support for how income households compared to last year (2012/13). However, households have already faced significant cuts since 2010/11. So in 2013/14 the government will be spending £16.5bn less on social security and tax credits than it was in 2010/11. The majority of these cuts impact on the finances of low income families.
CPAG adds that by 2014/15, the cumulative effect of cuts to social security and tax credits since 2010 will be £22bn annually relative to 2010/11.
The list of six does not include another major reform beginning this year - replacement of disability living allowance with personal independence payments - which will by 2016 save an estimated £1bn a year as an estimated 500,000 disabled people have their claim removed.
The CPAG calculation does not include a further non-dependent deduction increase in April 2013 for claimants in private rented accommodation, or the the social fund, which has cut and localised into 150 local welfare schemes which will offer food vouchers in lieu of crisis loans.
Nor does it include the biggest reform of all, Universal Credit, which will be tested in a handful of areas before being rolled out from October 2013. CPAG says it was not included because its mid-year introduction means it is too difficult to calculate its impact.
Universal credit intended to simply the benefit system by wrapping seven means tested unemployment benefits and tax credits into a single payment. The government argues that this will make it easier for claimants to afford to move from benefits into work.
The work and pensions secretary Iain Duncan Smith claims that 2.6m households will have higher entitlements as a result of universal credit, 1.3m of them by over £25 a week. He claims it will lift 350,000 children out of poverty, and that no one will be worse off under the new system. He says:
The early introduction of Universal Credit demonstrates our ongoing commitment to transforming the welfare system and will improve the lives of millions of claimants by incentivising work and making work pay.
But campaigners some groups will lose out: around 450,000 disabled people according to Disability Rights UK; while 400,000 of the poorest families - especially single parent households with children - will be worse off by 2015, according to the Chartered Institute of Housing.
The government argues that raising the personal tax allowance in April will offset the financial impact of some of these cuts. But CPAG says it will do little to help the poorest households:
The working poor generally rely on housing benefit and council tax benefit, so get 85% of the gain from the raising of the tax allowance taken away again because of tapers that mean their benefit is withdrawn as their income rises.
Alison Garnham, Chief Executive of Child Poverty Action Group, said:
Families already struggling with rising living costs face another body blow as a potentially devastating package of benefit cuts is introduced this month which will grab desperately needed financial help away from families and suck billions of pounds of spending power out of local businesses and communities.
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