The companies listed are predominantly large public service providers and essential infrastructure operators in South Australia. Many are government-related entities or long-established corporations crucial for the region's functioning, spanning healthcare, utilities, and transportation. SA Health, for example, focuses on public health services, while SA Water provides water and sewage services. Santos Ltd is a global energy company, and People First Bank is a member-owned bank.
The data shows a strong concentration of headquarters in Adelaide, indicating its role as the primary administrative and economic hub. Most of the companies have a substantial history, with many founded in the late 19th or early 20th century, such as the Royal Adelaide Hospital (1840) and SA Water (1856), suggesting a mature and well-established corporate landscape.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
SA Healthsahealth.sa.gov.au
SA Health is dedicated to improving the health of South Australians through public health services, research, policy development, and quality care with a focus on wellbeing and early intervention |
9,193 | |||
| 2 |
Santos Ltdsantos.com
Global energy company providing reliable, affordable energy; transitioning to lower carbon fuels, including oil, gas, and carbon capture solutions for homes and industries. |
6,628 | |||
| 3 |
Royal Adelaide Hospitalrah.sa.gov.au
Leading teaching hospital in South Australia providing exceptional medical care, rehabilitation, training, and research opportunities for staff in various specialties |
2,173 | |||
| 4 |
SA Watersawater.com.au
South Australia's top provider of water and sewage services, ensuring a reliable supply of safe, clean water and dependable sewerage system for 17 million people |
2,028 | |||
| 5 |
People First Bankpeoplefirstbank.com.au
A leading Australian member-owned bank, dedicated to people and their finances, with a friendly team and dual head offices |
1,897 | |||
| 6 |
Department for Infrastructure and Transportdit.sa.gov.au
A major organization managing assets, budget, and capital programs in South Australia, specifically focused on public transport investments and projects |
1,815 | |||
| 7 |
SA Power Networkssapowernetworks.com.au
Deliver electricity to 1.7 million customers, enable renewable energy solutions, ensure safety, and support South Australia's energy transition. |
1,794 | |||
| 8 |
ARTCartc.com.au
This company operates a modern rail network in Australia, investing in infrastructure and promoting diversity, safety, and innovation in the workplace |
1,427 | |||
| 9 |
Women's and Children's Health Networkwch.sa.gov.au
Provider of health services for women, children, and young people in South Australia, offering specialized care, community services, research, teaching, and policy development |
1,037 | |||
| 10 |
Kelsian Group Limitedkelsian.com
Australia's largest integrated transport provider and tourism operator, specializing in safe, sustainable, and intelligent transport solutions for communities worldwide |
971 | |||
| 11 |
SA Pathologysapathology.sa.gov.au
Statewide pathology provider in South Australia offering high-quality medical testing and research services 24/7, 365 days a year to patients and healthcare providers |
870 | |||
| 12 |
Central Adelaidecentraladelaide.health.sa.gov.au
Health network providing services in Central Adelaide with hospitals, rehabilitation, dental, pathology, medical imaging, pharmacy, and various statewide services |
806 | |||
| 13 |
SA Ambulance Servicesaambulance.sa.gov.au
Provider of high-quality ambulance care in South Australia, responding to over 200,000 incidents with a team of career and volunteer staff, operating a fleet of 300 vehicles |
803 | |||
| 14 |
ACHAacha.org.au
A healthcare alliance operating private hospitals in Adelaide, offering critical, neonatal, maternal care, angiography, acute cardiac units, advanced technology, and top-class medical expertise |
742 | |||
Want more companies than this list?This page shows the largest ones only. Connect to Tamtam to see every company that matches, filter by size, industry or growth, and reach their decision-makers. | |||||
| 15 |
Beyond Bank Australiabeyondbank.com.au
Customer-owned bank focused on financial wellbeing, social and environmental impact, driving positive outcomes for communities and planet. |
739 | |||
| 16 |
ACH Groupachgroup.org.au
A not-for-profit organization in South Australia supporting older individuals to thrive with innovative services that empower and value them |
734 | |||
| 17 |
Southern Adelaide Local Health Networksahealth.sa.gov.au
A healthcare organization in Southern Adelaide providing reliable, respectful care across the lifespan, including obstetrics, surgery, mental health, and end-of-life services |
684 | |||
| 18 |
Australian Gas Infrastructure Group (AGIG)agig.com.au
AGIG is a leading gas infrastructure business in Australia, distributing natural gas to over 13 million customers and promoting the transition to a sustainable future with Renewable Gas |
620 | |||
| 19 |
ElectraNet Pty Ltdelectranet.com.au
Specializing in electricity transmission, providing energy solutions across Australia with a focus on reliability and preparing for the future of power generation and consumption |
589 | |||
| 20 |
Eldercareeldercare.net.au
A leading aged care operator in South Australia, offering residential care, retirement living units, and person-centered initiatives with a focus on respect and dignity |
557 | |||
| 21 |
People's Choice Credit Unionpeoplefirstbank.com.au
Member-owned financial institution providing competitive products and services while reinvesting profits to benefit members, staff, and the community Inclusive and motivated team |
492 | |||
| 22 |
Beach Energy Ltdbeachenergy.com.au
Australian oil and gas business with a pioneering history, largest onshore oil producer, major gas operations across Australia and New Zealand |
487 | |||
| 23 |
Northern Adelaide Local Health Networksahealth.sa.gov.au
A healthcare organization in northern Adelaide providing hospital, community, and home-based services to enhance the quality of life for the community |
468 | |||
| 24 |
BankSAbanksa.com.au
A division of Westpac Banking Corporation in South Australia, with a history dating back to 1848, committed to supporting the state's future |
458 | |||
| 25 |
SeaLink Marine & Tourismsealink.com.au
The company provides integrated travel experiences, including ferry services, cruises, tours, and accommodation, connecting travelers to iconic destinations in Australia |
400 | |||
| 26 |
Jones Radiologyjonesradiology.com.au
A doctor-owned practice providing high-quality diagnostic and interventional radiology services in South Australia and Alice Springs, with a focus on subspecialisation and advanced technology |
340 | |||
| 27 |
Porsche Bank Groupporschebank.at
Offers leasing, credit, insurance, and maintenance for VW, Audi, SEAT, 艩KODA, and Porsche vehicles. Operates internationally in numerous countries. |
272 | |||
| 28 |
South Australian Metropolitan Fire Servicemfs.sa.gov.au
Primary provider of structural firefighting services in South Australia with over 1,000 professional staff and 36 stations across the state |
195 | |||
| 29 |
RDNS Silverchainorg.au
A pioneering not-for-profit organization providing high-quality health and aged care services at home, supported by research, technology, and compassionate care |
185 | |||
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 11, 2026.
More company lists in South Australia
- The largest companies in South Australia 273
- Multinational companies in South Australia 36
- Healthcare providers in South Australia 31
- Government Administration companies in South Australia 31
- Manufacturers in South Australia 25
The same list elsewhere in Australia
- Critical infrastructure operators in Australia 450
- Critical infrastructure operators in New South Wales 151
- Critical infrastructure operators in Victoria 123
- Critical infrastructure operators in Queensland 79
- Critical infrastructure operators in Western Australia 42
- Critical infrastructure operators in Sydney 63
- Critical infrastructure operators in Melbourne 51