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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Data summary

Welfare cuts Click heading to sort table. Download this data Number Reforms Implementation date Client groups affected Total cost to households Indicative loss per affected claimant 1 Child Trust Funds abolished May 2010. Young people £560m for 2013/14 £675 per family 2 Support for mortgage interest paid at Bank of England interest rates Oct 2010. Home owners +£10m for 2013/14 £11.30 per week 3 Education Maintenance Allowance (EMA) abolished Sep 2011. Young people 16-19 year olds in education £500m for 2013/14 £28 per week 4 WTC childcare cost support reduction in support from 80% to 70% April 2011. Working parents £350m for 2013/14 5 WTC and CTC withdrawal (taper rate) increase April 2011. Workers £730m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 6 WTC and CTC disregard for in year income increases reduced to £5K April 2013, with reductions to £10K in 2011 and 2012 in preparation Workers £455m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 7 WTC and CTC £2500 disregard for in year income falls April 2012. Workers £720m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 8 WTC and CTC new claims and changes of circumstance backdated only 1 month April 2012. Workers £355m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 9 CTC family element withdrawn for families on more than £40K April 2012. Working parents £125m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 10 CTC family element tapered immediately after child element April 2012. Working parents £440m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 11 WTC 30 hour element frozen April 2011. Workers full time £975m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 12 WTC basic element frozen April 2011. Workers 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 13 WTC single parent and couple element frozen for one year April 2012. Working parents £295m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 14 WTC 50+ element abolished April 2012. Workers over 50 £35m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 15 WTC minimum hours for couple rise from 16 to 24 April 2012. Working couples £545m for 2013/14 1.25% for the lowest income decile 0.75% for the 2nd decile 1% for the 3rd decile 1% for the 4th decile 1.1% for the 5th decile 16 CTC baby element abolished April 2011. New parents with babies under 2 £275m for 2013/14 £545 per year 17 Restricted Sure Start Maternity Grant to first child only April 2011. New parents £75m for 2013/14 £498 per family 18 Abolish health in pregnancy grant April 2011. New parents £150m for 2013/14 £380 per family 19 Extended conditionality for lone parents on income support IS may stop if your youngest child is over 5 Jan 2012. Non working mothers youngest child 5-7 years old £210m for 2013/14 £0 (but extra conditionality) 20 Housing Benefit: LHA cap April 2011 for all new claimants. Existing claimants on the anniversary of their claim, with nine months of transitional protection Renters in the private sector £225m for 2013/14 £12 per week 21 Housing Benefit: Removal of 5 bedroom rate April 2011. Large families in private rental sector £145m for 2013/14 £12 per week 22 Housing Benefit: Removing £15 excess benefits could claim if their rent was below LHA April 2011. Renters in the private sector £240m for 2013/14 £12 per week 23 Housing Benefit: LHA capped at 30th percentile rather than median April 2011. Renters in the private sector £445m for 2013/14 £12 per week 24 Housing benefit: shared accommodation rate for under 35s Jan 2012. Young renters 25 - 34 year olds £230m for 2013/14 £41 per week 25 Housing Benefit: Non-dependent deductions increase April 2011, and April 2012 and 2013 again Renters £195m for 2013/14 £13.70 per week 26 Council Tax Benefit: Non-dependent deductions increase April 2012. Renters Localised Localised 27 Contribution based ESA time limited April 2012. Sick or disabled former workers £835m for 2013/14 £52 per week 28 Abolished youth provision of ESA April 2012. Young people with disabilities £85m for 2013/14 £25 per week 29 Benefits indexed with CPI not RPI April 2011. All £4.88bn for 2013/14 (now uprated at 1%) 30 Frozen child benefit rates for three years April 2011. Parents £1.25b for 2013/14 £2.96 per week 31 Child Benefit. Household with one income £60k and above are no longer eligible Jan 2013. Parents in households with one earner earning over £60K £1.53b for 2013/14* (includes no.32) £1,300 per year (higher income earners only) 32 Child Benefit. Taper for households with an income over £50k Jan 2013. Parents in households with one earner earning over £50K £1.53b for 2013/15* (includes no.31) £1,300 per year (higher income earners only) 33 Benefit cap £500 per week for couple and lone parent households, £350 for singles From April 2013 (phased roll out by LA) Large families, families in high rent areas £290m for 2013/14 £93 a week 34 Housing Benefit: Linking LHA increases to CPI 2013-14 Renters in the private sector £90m for 2013/14 £6 per week 35 Housing Benefit: Bedroom tax for under-occupation of social housing April 2013. Renters in the social sector with spare rooms £490m for 2013/14 £14 per week 36 Localisation of Council Tax Benefit with a 10% cut April 2013. All £485m for 2013/14 £2.64 per week 37 Replacement of DLA with Personal Independence Payments April 2013-2016 People with disabilities £1.02b a year when in steady state £16.81 per week overall 38 Transfer to Universal Credit October 2013- 2017 All JSA / ESA / IS/ WTC/ CTC claimants +£100m a year when in steady state +£16 per week 39 Benefits uprated by 1% rather than CPI (JSA, ESA, ISA, CTC, WTC) April 2013. All £505m for 2013/14 £3 per week 40 Child benefit uprated by 1% between 2014/15 and 2016/17 April 2014. Parents £175m for 2014/15 £3 per week 41 LHA increased by 1% between 2014/15 and 2016/17 April 2014. Renters in the private sector £105m for 2014/15 £3 per week 42 Increase earnings disregard in UC by 1% rather than CPI for 2 years April 2014. Workers £170m for 2014/15 £3.20 per week

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