The Coalition will cut $4.5bn from foreign aid and is assuming another $1.1bn in savings from quickly 'stopping the boats' to claim it will leave the budget a modest $6bn better off than Labor over four years.

It is also claiming a $1.1bn "growth dividend" from abolishing the carbon tax, but says it has not included this in the calculations of its budget bottom line.

Finally releasing the Coalition's costings just two days before the federal election, shadow treasurer Joe Hockey said they "put a lie to [Kevin] Rudd's claim of a black hole of $70bn" and contained no net cuts to health or education.

But the figures also reveal that, based on Treasury forecasts, the Coalition would not return the budget to surplus any faster than Labor is scheduled to do – despite its insistence that Australia is facing a "budget emergency".

A letter from the three "wise men" appointed by the Coalition to review its costings – former head of the prime minister's department Peter Shergold, former Queensland auditor-general Len Scanlan and co-founder of Access Economics Geoff Carmody – said they were "based on reasonable assumptions and calculations" and "represent a fair estimate of the net financial impact" of the policies.

The documents released on Thursday reveal another $9bn in cuts, which, after election spending is taken into account, leave net savings of about $6bn across the next four years.

The many road-funding announcements around the nation that Tony Abbott hopes will earn him the moniker of "infrastructure prime minister" total $11.5bn. Some $6.13bn of that money comes from redirecting existing roads funding in the budget, but another $4.6bn comes from axing federal funding for public transport, including the Melbourne metro rail, the Brisbane cross river rail, Perth urban rail public transport and the Tonsley Park public transport plan for Adelaide.

The Coalition is also further putting off Australia's already deferred promise to raise foreign aid spending to 0.5% of gross national income and says its foreign aid policy will shift money from "non-government organisations" to "on the ground" aid provision.

Hockey said the intention was to "cut growth in foreign aid to pay for more infrastructure here in Australia".

The Coalition is claiming $1.08bn in savings on the assumption that the number of asylum seekers arriving by boat will fall to 370 a month by the end of 2014 and to just 50 a month by 2016. It also assumes a benefit of $1.3bn from unpaid interest on money it will not be borrowing for the national broadband network and the clean energy finance corporation.

The Coalition is saving $428m from yet another "efficiency dividend" on the public service, on top of efficiency dividends already imposed by Labor and the Coalition's separate intention to save money by cutting 12,000 federal public servants.

And it will save $650m from a previously unannounced plan to put off water buybacks for the Murray-Darling basin.

The costings reveal that the Direct Action fund to tackle climate change will not start making grants until 2014-15, so the Coalition is committing only $1.5bn to its climate change policy over the next four years.

The Coalition has refused to promise that it will deliver a budget surplus in any particular year on the basis of the costings it has provided because it says it does not believe the bottom line figures produced for the government by the Treasury at the beginning of the election campaign.

But if the Coalition's reckoning is applied to those budget figures it would not return the budget to surplus until 2016-17, the same year Labor is forecasting a modest budget surplus.

The Coalition says it will pay down $16bn in debt, including $9bn it will not be borrowing for the NBN and clean energy.

Most of the costings were submitted to the parliamentary budget office, but the detailed costings provided by the office were not released. The Direct Action plan, the border security policy and the national broadband policy were not submitted to the PBO.

Labor strategists questioned how the coalition could claim a "saving" of $200m for a small business tax break that Rudd announced as a Labor policy only last Sunday and which is therefore not included in the federal budget at all.

And they pointed out that cuts to government co-contributions for low income earners superannuation were being booked to save $961m in this financial year, which they said made it in effect retrospective.

Greens leader Senator Christine Milne said Abbott had not had the courage to cost or model Direct Action because it was a "slogan" and a "joke" and could never deliver Australia's promised greenhouse gas emission reductions. She accused the Coalition leader of taking money from the world's poorest people to build Australian road tollways.

The community and public sector union, which represents federal public servants, said the additional efficiency dividend would probably mean an additional 6,250 job losses, on top of the 12,000 already announced.