One of the core announcements of George Osborne’s Conservative party conference speech was a pledge to freeze all working-age benefits – which includes out-of-work benefits, tax credits, child benefit and others – for two years. This, he said, would save about £3bn a year.

The move may be tough for families – the majority of them being in work – that have already endured lower rates of benefits increases under the coalition, the introduction of the bedroom tax, the £26,000 (now proposed to drop to £23,000) benefits cap and other such measures.

What other ways might Osborne have chosen to achieve similar savings?

1. Eliminate the buy-to-let tax subsidy

Ever since the then chancellor, Gordon Brown, eliminated the mortgage tax break in 1999, you’ve had to pay tax on the interest on the mortgage of your own home. But if you’ve bought a property to rent out, your mortgage interest payments are tax deductible – a considerable break if you pay the higher rate of tax. This “upper-middle class perk” costs the exchequer in excess of £5bn a year.

Savings: £5bn-£7bn a year

2. Means-test the winter fuel allowance

Older people receive a lump sum of between £200 and £300 each winter, to spend on what they wish, under the “winter fuel allowance” introduced by Brown. This is received whatever their financial circumstances, even if they are millionaires. One parliamentary report suggested means-testing the benefit to pensioners on lower incomes would save considerable sums.

Savings: £1.7bn a year

3. Reverse Osborne’s corporation tax cuts

Throughout his term as chancellor, Osborne has repeatedly slashed corporation tax. Advocates hoped the boost to business competitiveness would offset the lost tax revenue, but to date that’s not proven to be the case, and the cost of the cuts has had to be recouped from elsewhere.

Savings: £5bn a year

4. Scrap Trident

The cost of maintaining and replacing Britain’s nuclear deterrent is hotly contested by the system’s advocates and its equally passionate detractors. But between running costs and a one-off £20bn to £30bn spend to replace the current ageing missile range, scrapping the system would save serious cash.

Savings: £2bn-£4bn a year

The Faslane submarine base east of Glasgow, home to the UK’s Trident fleet. Photograph: Murdo Macleod

5. Abolish HS2

The High Speed 2 rail lines are currently forecast to cost £43bn, plus another £7.5bn for rolling stock, over the course of the construction project. Though, as these costs have increased several times before work has even begun, opponents say they could increase still further. Scrapping the scheme would save billions, though could still be a mistake if you believe the figures for the estimated benefits it would bring.

Savings: £50bn+ over 30 years

6. Revoke statutory sick pay and maternity pay

This would likely be an unpopular move for the chancellor, but sick pay and maternity pay (combined) are the working-age benefits that make the closest comparison to the amount Osborne is planning to trim from the benefits bill. The social fund and carers’ allowance both cost less, while the jobseeker’s allowance (£4.9bn) and employment and support allowance cost a little more. The largest single benefit is, of course, the state pension.

Savings: £3.6bn a year

7. Gradually reduce the stake in RBS

The UK taxpayer still owns 80% of the bank which, based on today’s share price, is worth just under £33bn. Selling a portion of this holding each year – if the price held, which it probably wouldn’t, but in the long run shares go up more than down – would raise considerable funds over more than a decade.

Savings: £3bn a year for 11 years, at today’s price