Suburban Rail Loop cost: $50bn promised, $96.4bn forecast

The Suburban Rail Loop cost was up to $34.5 billion for the first stage alone, and the government now says $33.3 billion. Victoria's Auditor-General said in August 2026 that stage could top $36 billion, and the Parliamentary Budget Office put two stages at $96.4 billion in 2024. The whole loop was promised for $50 billion in 2018.

None of those numbers is a final bill. The loop is years from finished, and there is no current estimate for all of it: the last full figure on the record is $88 billion, in 2020 advice to the government reported by the Auditor-General. What follows is every figure, what each one actually measures, and what the Auditor-General found when it checked.

Suburban Rail Loop cost: every figure, and what it measures

The numbers look like they contradict each other. Mostly they don't: they are measuring different things. Some cover one stage and some cover two. Some stop when building stops, and others run to 2084.

The Parliamentary Budget Office's 2022 advice included a figure of $125.0 billion, but that wasn't a price to build the loop. It was for "asset works and renewals", and the Budget Office said in March 2024 that the 2022 advice hadn't split building from operating.

What the Auditor-General found

The Victorian Auditor-General's Office (VAGO) tabled its audit of SRL East on 26 August 2026. Its headline finding was that the project is "unlikely to be delivered on budget and on time".

SRL East is "more likely than not to exceed its publicly disclosed cost of up to $34.5 billion", VAGO found. Its estimate of the potential final cost was $36,077.8 million, about $1.7 billion above the Suburban Rail Loop Authority's (SRLA) December 2025 budget.

VAGO called that estimate "conservative". According to the audit, the $36 billion also doesn't include:

• At least $1.6 billion for station interchanges at Southland, Glen Waverley and Box Hill, the tunnels that let passengers change to the existing Metro lines. VAGO said only $104 million of the $1.7 billion total is in the budget.
• $500 million to $750 million to buy about 21 strategic development sites.
• About $3.9 billion for the first 15 years of operating and maintaining the line, under a franchise signed in December 2025. VAGO said leaving this out is consistent with how other big rail works are funded.
• About $300 million in early development costs, which VAGO said the $34.5 billion also leaves out.

VAGO blamed three things for the cost pressure: ground conditions and contamination, higher than expected market prices for the Linewide and stations packages, and government decisions to slow spending "to manage the state's debt levels". Those decisions, it found, added cost and delay.

The contingency is going too. SRLA's estimates included $9.5 billion, or 29 per cent, for unforeseen risks. VAGO said a "significant portion" has been used, though SRLA "claims it has enough contingency remaining".

SRLA rejects the findings. In its response, published in the audit's Appendix A, SRLA said: "The Report presents assumptions as established facts, creating a distorted, unbalanced narrative that is not supported by the evidence." It said the interchanges and the Glen Waverley car park were "potential future scope options, not approved project costs". VAGO said the government approved the interchanges in October 2020, but hasn't funded building them.

SRLA didn't accept any of the six recommendations VAGO directed to it. Treasurer Colin Brooks said on 26 August 2026: "The SRL East will be delivered on time and on budget," the ABC reported.

The fare levy nobody announced

The audit also revealed something commuters had never been told. Since 1 January 2025, VAGO found, Victorians have been paying a levy called the rail improvement charge: an extra 1 per cent a year on public transport fares, on top of the annual CPI rise.

The government planned to put 60 per cent of the money towards SRL East, an amount the Department of Treasury and Finance estimated at $4.8 billion in net present value terms to 2062. VAGO said that would make it "the project's largest source of value capture revenue". Value capture is meant to charge the people and businesses who benefit from a project. VAGO said this levy would "collect revenue 9 years before public transport users will experience any benefits".

The audit sets out how that happened. The government first approved the levy in August 2021, and in November 2024 it approved "excluding any reference to the rail improvement charge from public communications on the value capture package". As at June 2026, VAGO said, the government still had not announced it.

The Department of Premier and Cabinet and the Department of Treasury and Finance disagree, telling VAGO the charge "does not form part of the SRL East Funding and Financing Strategy". Premier Ben Carroll said on 27 August 2026 he would scrap it "because there was no transparency in its creation and implementation", the ABC reported. Deputy Premier Gabrielle Williams said it "has not met the pub test". The ABC reported the levy had raised about $6.5 million so far, and reported on 30 October 2026 that the surcharge will cease on 1 January.

Who pays: the $5.5 billion gap

The plan was three equal shares of about $11.5 billion: the state Budget, the Australian Government, and value capture. According to VAGO, that plan has a hole in it.

At June 2026 there was "a $5.5 billion gap in the project's approved funding", the audit said. Victoria has asked Canberra for $11.5 billion, and Canberra has committed $6 billion. VAGO also reported "significant uncertainty" that money from sources other than the state Budget and debt will be fully achieved.

Scrapping the levy removes what VAGO called the largest source of value capture revenue, though the government disputes that the levy was part of the plan. VAGO said the Treasury and Premier's departments have advised the government since 2019 that the state Budget "cannot fully fund the project's expected $34.5 billion cost without limiting spending in other areas and missing its fiscal targets". Victoria's debt is forecast to reach $197 billion in 2029-30, the ABC reported on 30 October 2026.

SRLA had spent $5.7 billion as at 31 December 2025, according to VAGO.

The savings

On 25 August 2026, the day before the audit landed, Premier Ben Carroll announced he would cut SRL East to $33.3 billion, with a review to find another $1 billion. "The SRL will be built on time. Today's changes mean it will be built under budget," he said, The Nightly reported.

The cuts include the underground interchanges at Box Hill and Glen Waverley, a second station entrance at Clayton, and pedestrian bridges at Burwood and Cheltenham, according to the same report.

The audit raises a question about those savings. VAGO found $104 million was budgeted for all three interchanges, against a total cost of $1.7 billion, and the ABC reported that the estimated total never included the interchanges. On those figures, dropping two avoids a future bill but appears to take little off the published cost. The $1 billion also comes from the other cuts, and the government hasn't itemised them: Carroll said further details were commercial in confidence, the ABC reported on 27 August 2026.

A government spokesperson said avoiding "unnecessary scope" would reduce the total to $33.3 billion, the ABC reported. The government also rejected VAGO's view that the project was unlikely to be delivered on time and on budget. VAGO's $36 billion was based on evidence from before these cuts, so the two figures aren't directly comparable.

Who's to blame?

Labor owns the Suburban Rail Loop: Daniel Andrews promised it in 2018, and Labor has held government ever since. VAGO's findings are about decisions by the government and its agencies, and don't name individuals.

The Coalition hasn't had a steady answer either. Liberal leader Jess Wilson said in May that construction would stop during a review, with workers still paid, according to the ABC. After the government said pausing would cost at least $1 billion, the Coalition backtracked on 30 October 2026, saying the pause meant "not committing to further contracts whilst the review about the project's future is undertaken". It says the review would be finished in its first 100 days. Carroll's own review also means no more contracts will be signed until it is complete, The Nightly reported.

Canberra is part of this too. Infrastructure Australia said in January 2025 that it had "low confidence in the cost estimate for SRL East" and recommended the Australian Government get a full funding strategy before committing more. The federal government added $3.8 billion in May 2026, VAGO reported, taking its commitment to $6 billion.

What we're getting for it

SRL East is 26km of twin tunnels with six new underground stations between Cheltenham and Box Hill, linking suburbs that today mostly connect by rail only through the city. The government has committed to running trains by 2035, and SRLA forecasts services from 31 December 2035. VAGO called that target "unlikely" to be met, and SRLA "strongly rejects" that conclusion.

The business case for East and North found a benefit-cost ratio of 1.1 to 1.7, using a 4% discount rate. On that measure, every dollar spent returns more than a dollar in benefits. Infrastructure Australia said in January 2025 that the results were "overstated", and the Parliamentary Budget Office found in September 2024 that at Infrastructure Australia's central 7% rate the ratio falls to between 0.6 and 0.7, a net cost to society. At 4%, with all benefits counted, the Budget Office got 1.2 to 1.4.

Infrastructure Australia's Priority List currently rates SRL East "Investment ready", and says it aims to address the strain from Melbourne's "monocentric urban form". That's the fair case: Melbourne is growing, and middle and outer suburbs have long been poorly served by a rail network built to run in and out of the city.

Your share: VAGO's potential final cost of $36.1 billion works out to about $5,050 for every Victorian, an Aussie Outrage calculation using the ABS population of about 7.15 million at March 2026. The $96.4 billion for two stages is about $13,500 each. Part of the bill comes from federal taxes paid by all Australians.

Victorians vote on 28 November. This is part of a series on the cost of the Big Build: see the $15 billion question on alleged Big Build corruption, North East Link's $26 billion bill, the cancelled Commonwealth Games and the blowout leaderboard.