CGT, VAT, public pensions... Prime Minister David Cameron has already warned today's emergency Budget will likely contain some of the harshest measures since World War II.
So what are they likely to be?
The coalition Government has already announced plans to increase CGT from its current level of 18% to closer to 40% for non-business assets, such as second homes, buy-to-lets and shares. But there are concerns over the Treasury's ability to distinguish between a business and a non-business asset.
Accountants PricewaterhouseCoopers (PwC) say Osborne may unveil a higher rate of up to 50% for those assets held for the short term (one or two years) and a lower rate of 30% for those assets held for a longer period.
Expected to rise from 17.5% to 20% - a move which, according to shopping comparison site Kelkoo, could cost UK households an extra £1.16 a day, or £425 a year.
Little has so far been said on inheritance tax, but any changes to CGT will affect IHT planning, particularly for those who want to give away investment assets.
The state of the UK economy doesn't exactly make for happy reading: Debt has risen above £900bn, the new Office for Budget Responsibility has downgraded the 2011 growth forecast from 3.25% to 2.6%, and the deficit currently stands at 10.4% of GDP. For today's Budget, Cameron's team talks about a mix of 80% spending cuts and 20% tax increases.
Analysts polled by Reuters expect gilt issuance in 2010/11 to be revised down to £165bn, more than £20bn lower than forecast in March and some £60bn less than in 2009/10.
National insurance contributions (NICs)
The Conservatives scrapped Labour's proposed 1p rise to employers' NICs, but the employees' 1p rise will apparently be preserved. It is expected the employers' threshold for NI will rise slightly - by £21 - and there will be measures to ease the NI burden on small start-up businesses.
Cuts in the main rate of corporation tax from the current 28% have been promised, but the plan to pay for them with cuts in capital allowances and reliefs has upset those (manufacturers especially) who would lose out, so may go out for further consultation.
Small business start-up tax relief
The Chancellor is expected to hand new businesses a £900m boost with a one-year NIC holiday on the first 10 staff they employ. However, George Osborne will ban businesses in London, the south-east and the east of England from applying for the tax break, worth up to £50,000 for each business.
'Time to Pay' scheme
There are widespread fears the scheme, which has so far helped more than 200,000 businesses ease their cash flow problems by allowing them to defer over £5bn in tax payments to HMRC, will become a casualty of the first Budget of George Osborne's "Age of Austerity".
Osborne admitted at the weekend the Budget will include a bank tax, which he estimates could raise as much as £3bn by asking banks to pay a levy based on the size of their balance sheets.
The income tax allowance is generally expected to rise to around £10,000, up from the current tax-free limit of £6,475. An initial increase of £1,000 from next April (worth £200 to basic rate taxpayers) is on the cards.
It is unlikely higher rate taxpayers will benefit in full (e.g. an adjustment worth 20%, not 40%), similarly those aged over 65.
IFAonline readers can follow all today's developments, including news, reaction and analysis, on the site from 12.30pm.
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