By ITV News Multimedia Producer Charlie Bayliss
From possible tax rises, freezes and cuts, the chancellor is tasked with reviving Britain's struggling economy which is currently saddled with around £2 trillion of debt.
Here's what we know so far, what to look out for and how it might affect you.
The furlough scheme is to be extended until the end of September, with employers asked to contribute to workers’ salaries from July.
Addressing MPs in the Commons, the chancellor will pledge to continue to help businesses and individuals through the “challenging months ahead – and beyond”.
He is expected to say the Coronavirus Job Retention Scheme - which has protected more than 11 million jobs since it began - will keep going until the autumn.
However the government’s contribution to the scheme - which is estimated to have cost around £60 billion - will be tapered off from July.
Employers will be asked to pay in alongside the taxpayer to help fund the cost of furloughed employees.
In July, employers will be expected to contribute 10%, increasing to 20% in August and September, as the economy reopens. Employees will continue to receive 80% of their salary for hours not worked until the scheme ends.
Self-Employment Income Support Scheme
A fourth grant from the Self-Employment Income Support Scheme (SEISS) will be available to claim from April, worth 80% of three months’ average trading profits up to £7,500.
The Treasury said that hundreds of thousands more people will be eligible for the grants this time, as tax return data for 2019/20 is now available.
Mr Sunak faced criticism that newly self-employed people were unable to benefit from the scheme previously.
The cut in Value Added Tax (VAT) to 5% from 20% is expected to come to an end in March.
But the Daily Mail and FT both report the temporary tax break could be extended to June.
Food, drink and holiday businesses all benefited from the 15% slash in VAT rates.
An extension of the reduced rate could encourage spending once restrictions are lifted, as theoretically things will be cheaper to buy.
ITV News Political Editor Robert Peston has said he expects the £20 uplift to Universal Credit to continue for another six months.
The temporary measure was first announced at the start of the coronavirus pandemic in the UK to help struggling families. In total, it is worth around £1,040 a year.
According to Robert Peston, the Treasury is reluctant to make the top up permanent because, with the knock-on impact on tax credit, it costs around £6 billion a year.
The policy announcement is subject to final approval from the prime minister.
Grants for pubs, bars, restaurants and gyms hit hardest by Covid
Pubs, restaurants, shops and other businesses hit hard by Covid-19 will be eligible for a £5bn grant scheme to help them reopen as lockdown is eased.
Mr Sunak will announce "restart grants" worth up to £6,000 per premises will help non-essential businesses get back on their feet.
Hospitality, hotels, gyms, as well as personal care and leisure firms, will be eligible for up to £18,000 per premises as they are due to open later under the plans for easing lockdown.
The Treasury estimates 230,000 firms will be eligible for the higher band, which will be awarded based on their rateable value, and 450,000 shops will also be able to apply.
The £5 billion is targeted at England, but the devolved nations in Scotland, Wales and Northern Ireland will receive an extra £794 million in funding through the Barnett formula.
Mr Sunak said: “Our local businesses have been hit hard by the pandemic which is why we went big and went early with a multibillion-pound package of support.
“There’s now light at the end of the tunnel and this £5 billion of extra cash grants will ensure our high street can open their doors with optimism.”
It has also been revealed there will be a £1.65 billion boost for the coronavirus vaccine rollout programme to ensure it meets its target of offering a first dose to every adult in the UK by July 31.
Reports suggest the Chancellor will extend Stamp Duty Land Tax holiday in England which has helped prop up the housing market throughout the pandemic.
The saving, which cuts the tax bill entirely on properties costing between £125,000 and £500,000 and reduces it on homes costing more than that, was announced last summer and is due to end on March 31. This could save home-buyers up to £15,000 each.
However Mr Sunak is rumoured to be extending that deadline for up to three months until June.
Critics of the extension claim the tax break has lead to a boom in house prices.
Halifax said house prices rose by 7.6% in the year until November, with Nationwide reporting a similar figure of 7.3% growth - despite hundreds of thousands of Britons losing their job and the economic uncertainty caused by the coronavirus pandemic.
And with government support for the Coronavirus Job Rentention scheme expected to come to an end later this year, there are fears thousands more could end up unemployed, leading to a dip in house prices.
Mr Sunak is expected to announce the continuation of business rates relief beyond the end of March.
The business rate relief holiday was due to come to an end at the end of March and will provide a lifeline to businesses in the retail, hospitality and leisure industry.
Business rates are charged on most domestic properties such as shops, offices, pubs, warehouses, factories, holiday rental homes or guest houses.
The Scottish government made a similar pledge to keep business rate relief in place for another year.
The Chancellor looks set to shelve plans for a 5p increase in fuel duty, according to the Daily Mail.
Currently the levy stands at 57.95p per litre on petrol, diesel, biodiesel and bioethanol.
You also pay the standard VAT of 20% on most fuel, or the reduced rate of 5% on domestic heating fuel.
Mortgage Guarantee Scheme
A mortgage guarantee scheme aimed at helping aspiring homeowners with small deposits onto the property ladder and firing up the market is set to be announced.
Under the new plans, buyers will be able to purchase properties worth up to £600,000 with a deposit of just 5%.
The scheme will be open to both first time buyers and current homeowners.
The scheme, which will be subject to the usual affordability checks, will be available to lenders from April.
Lenders are typically less likely to approve mortgages when such a small deposit is put down, due to fears the home buyers will not be able to pay the full amount back.
The economic impacts of the coronavirus pandemic mean that low-deposit mortgages have "virtually disappeared", according to the Treasury.
The government plans to incentivise lenders to provide these low-deposit mortgages by offering them the guarantee they require to provide mortgages covering the remaining 95%.
The chancellor is also set to announce a £126 million boost for apprenticeships which he will claim will enable the creation of 40,000 additional traineeships in England.
At the same time, the Tory MP will promise to increase the cash incentives for employers who take on an apprentice to £3,000 – regardless of age.
Currently firms can claim £2,000 for each apprentice they hire aged 16 to 24, or £1,500 for those aged 25 and over.
Mr Sunak will also set out plans for new “flexi-job” apprenticeships, enabling trainees to develop their skills with a range of employers within a particular sector.
Instead of having a single employer, they will be linked to an agency that will place them with various relevant organisations.
From July, employers will be able to bid for money from a £7 million fund to create new agencies, with the first apprenticeships expected to start in January 2022.
Mr Sunak is also expected to announce the creation of a dedicated unit to crack down on Covid-19 fraudsters exploiting financial support, such as the furlough scheme.
The Taxpayer Protection Taskforce, underpinned by £100 million and 1,250 staff, will investigate and hunt down people swindling cash through coronavirus income support programmes, said the Treasury.
It is thought the UK-wide unit will be part of a series of anti-Covid fraud measures which the chancellor will announce.
Other expected announcements include new measures to crack down on fraud in the Bounce Back Loan Scheme.
There is speculation the Chancellor could look at increasing Capital Gains Tax, although nothing has been confirmed.
The levy is paid on the profit when you sell an asset which has increased in value. It is the gain which you have made which is taxed, not the amount you receive.
For example, if you bought a painting for £5,000 and sold it later for £25,000, it means you've made a gain of £20,000.
You are taxed on this if you sell the item, give it as a gift, are receiving compensation for something or swapping it for something else.
Britons currently have a tax free allowance of £12,300 per year, or £6,150 for trusts, with some assets not subject to any taxation.
Mr Sunak is also reportedly weighing up whether to increase corporation tax rates.
The chancellor is expected to announce a rise on the current rate of 19% over the parliament.
Business Secretary Kwasi Kwarteng, when speaking to ITV News, suggested corporation tax will not rise in this year's Budget.
"I'm not sure that's something that will necessarily happen tomorrow - clearly businesses have been supported a great deal and so there's an argument that says maybe in the future they can be expected to support/contribute to the tax revenue.
"That's a debate I think for another day," he said.
Officials are said to be keen on keeping Britain's business rates "competitive", according to the FT.
A change in tax rates would reverse cuts made under former Chancellor George Osborne, which led corporation tax to fall from 28% to 19%.
The UK currently has one of the lowest corporation taxes in the G7.
’Help to Grow’ scheme for small businesses
The Chancellor will announce a £520m initiative to support small businesses with training and software in this week’s Budget.
As many as 130,000 SME (small and medium enterprises) could be more productive by providing access to some of the UK’s top business schools.
The Treasury said firms will receive expert technology advice and discounted software to help spark innovation during the recovery from the pandemic.
Mr Sunak said: “Our brilliant SMEs are the backbone of our economy, creating jobs and generating prosperity - so it’s vital they can access the tools they need to succeed.
“Help to Grow will ensure they are embracing the latest technology and management training, fuelling our Plan for Jobs by boosting productivity in all corners of the UK.”
Arts boost for British businesses
Museums, theatres and art galleries will be given £400m of additional support to help them survive until the end of lockdown.
Under the government’s plans, many cultural attractions will remain closed until May 17 at the earliest, with many having been closed since March last year.
What time is the Budget statement?
Rishi Sunak is due to make his Budget statement at 12.30 on Wednesday 3 March.
You can watch live coverage of the Budget in an ITV News special programme on Wednesday from 12.15 on ITV and itv.com/news.
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