The Building Societies Association wants a First ISA scheme, with the government chipping in a first-year incentive. If the government paid 20p per £1 saved up to a cap of £100 per saver, it would the cost the Treasury a paltry £70m, falling to £35m a year, but would create half a million new savers in the first year and then 140,000 every year, the BSA claims.
ISA providers report to the taxman the National Insurance number and account details for each saver holding an ISA every year, so HMRC could identify first-time savers.
The BSA also wants rules simplified to make it easier for low-income savers to get a 10p savings tax refund, and for non-taxpayers to register for gross interest. Building societies are also repeating their past call for an increase in the subscription limit on cash ISAs to equal that of stocks and shares ISAs, and for unlimited transfers in either direction.
The BSA's chief executive, Robin Fieth, said: "Savers know the ISA brand so it makes sense for it to be used for a scheme which aims to grow the number of consumers who have some kind of savings buffer. Clearly, no single scheme is capable of fixing the UK savings culture, but it's a step in the right direction."
Nationwide backs those measures, and also wants a more generous ISA limit for first-time homebuyers who saving in a dedicated ISA towards a deposit.
The society also suggests stamp duty should be tiered, not imposed in a slab, to "overcome the current distortions created in the housing market".
The Chancellor may offer some consolation to low income savers by allowing small pension pots, perhaps up to £40,000, to be refunded in cash rather than used to buy a tiny annuity. It could benefit 150,000 people a year.
Tom McPhail at Hargreaves Lansdown says: "Reforming the small pots rule will help to unlock improvements right across the pension system. Small investors will get their money back, insurers will be able to sell better value annuities to large customers, and it will help to minimise auto-enrolment opt-outs."
Hargreaves also suggests a Long Term Care ISA, which could be passed on to dependants if not needed to fund nursing.
Meanwhile, the 40p tax rate is now catching one million more people than it did three years ago, according to the Institute of Fiscal Studies.
The rate will kick in at £31,866 in 2014-5.
Ronnie Ludwig, tax expert at Saffery Champness in Edinburgh, says: "Although pulling more people into higher tax is the Chancellor's way of paying for the increase in the personal allowance, he may feel that with the next election looming, now is the time to ease the burden."