Despite the continued strained economic climate, we’ve seen some big chunks of change thrown around in 2025.
While early-stage funding stayed constrained for much of the year, large cheques concentrated around a smaller group of companies certainly prevailed. In some cases, twice.
These were some of the largest Australian startup raises of 2025, and the companies that secured them. And in news that will surprise no one, there aren’t many women in the mix.
Firmus: $330 million and $500 million
September and November 2025
AI infrastructure startup Firmus raised $330 million in September as it accelerated plans for ‘Project Southgate’, a national network of AI data centres designed to support energy-intensive compute workloads.
If that weren’t enough, it went onto raise another cool $500 million just a few months later.
Originally founded as a bitcoin mining business, Firmus has repositioned itself around what it calls “green AI factories”, pitching sovereign AI infrastructure as both an economic and national capability issue.
Backed by Nvidia and data centre partners, the raise positioned Firmus among the largest beneficiaries of surging demand for AI compute in 2025.
Airwallex: $466 million and $498 million
May and December 2025
Apparently, one raise wasn’t enough for Airwallex, either. Back in May, the Melbourne-founded fintech Airwallex raised a blockbuster $466 million Series F, pushing its valuation to $9.36 billion.
Just six months later, it returned with $498 million in Series G, lifting that valuation to $12 billion and delivering the single largest combined fundraising effort by an Australian startup in 2025.
Airwallex has spent the past decade building global payments, banking, and treasury infrastructure for businesses operating across borders.
In 2025, it also signalled a shift toward embedding AI agents directly into financial operations, betting that autonomous finance will underpin its next phase of growth as it scales aggressively in the US ahead of a likely IPO.
Synchron: $305 million
November 2025
Medtech startup Synchron secured $305 million in Series D in November, with $54 million provided by the National Reconstruction Fund.
Originally spun out of the University of Melbourne, Synchron is developing a non-surgical brain implant that allows people with paralysis to control digital devices using thought alone.
The funding will support the next phase of clinical trials and regulatory work as Synchron works toward commercial deployment of its Stentrode device in the US.
Harrison.ai: $179 million
February 2025
The funding is being used to scale its diagnostic platforms globally, including Annalise.ai, which is now deployed across more than 1,000 healthcare facilities in 15 countries.
Harrison.ai’s technology has reportedly demonstrated improvements in the early detection of serious conditions such as lung cancer. The company was also at the centre of debates around how AI can expand healthcare capacity and how patient data should be governed as those systems scale.
RayGen: $127 million (sort of)
April 2025
After a 12-month process, RayGen completed its Series D in April. This brought the total raise to $127 million after an initial $51 million tranche in 2024 and subsequent top-ups from strategic energy investors and ARENA.
The Victorian startup develops next-generation solar and long-duration thermal storage technology, with operating projects in Victoria and large-scale developments underway in South Australia and overseas. Its Carwarp facility can deliver up to 17 hours of continuous power to the grid.
Heidi Health: $98 million
October 2025
Melbourne-based AI healthtech Heidi Health raised $98 million in a Series B round in October, just seven months after topping up its Series A.
The raise pushed Heidi’s valuation to $704 million and highlighted investor appetite for healthcare tools that tackle administrative burden at scale.
Heidi’s platform transcribes and processes clinician–patient conversations into clinical notes and follow-up materials, with usage now spanning more than 200 medical specialties across 116 countries.
Morse Micro: $88 million
September 2025
Sydney deep tech company Morse Micro raised $88 million in a Series C in September, including $35 million from the federal government’s National Reconstruction Fund (NRF).
The company designs long-range, low-power Wi-Fi HaLow chips for IoT devices, with applications across agriculture, mining, energy and smart infrastructure.
The funding is being used to accelerate the commercialisation of the chips as global demand grows for low-power, long-range connectivity across industrial, agricultural and infrastructure applications.
Lorikeet: $54.4 million
August 2025
AI customer support startup Lorikeet raised $54.4 million in a Series A in August, its third funding round in less than 12 months.
The Sydney-founded startup builds AI ‘concierge agents’ reportedly capable of resolving complex customer issues end-to-end across chat, email and voice.
Lorikeet’s customers include Airwallex, Linktree and Eucalyptus, with the startup positioning its AI agents as tools that can resolve issues end-to-end rather than deflect customers to self-serve workflows.
IND Technology: $50 million
December 2025
Energy technology startup IND Technology raised $50 million in December in its first institutional funding round.
Founded after the Black Saturday bushfires, IND develops early fault detection systems that identify electrical failures before they escalate into outages or fires.
IND is now focused on scaling the deployment of its early fault detection technology across utilities in Australia and overseas.
Vaxxas: $49.2 million
August 2025
Brisbane-based biotech Vaxxas raised $49.2 million in a Series D as it continues the development of its needle-free vaccine delivery technology, HD-MAP.
The raise came amid leadership changes and workforce cuts, reflecting the tougher funding environment for biotech in 2025.
Vaxxas is now focused on advancing HD-MAP through clinical trials while building out the manufacturing capability required for commercial use.
- This story first appeared on SmartCompany. You can read the original here.
