McMahon Services is seeking an experienced Senior Estimator to join our Engineering & Projects team in Adelaide.

This is an exciting opportunity to play a leading role within our Precontracts team, delivering complex, multidisciplinary tenders and helping secure major project wins across Australia.

You’ll work across medium to large-scale opportunities spanning Water, Defence, Resources, Industrial and Energy, with projects incorporating disciplines such as civil, structural, mechanical and piping (SMP), and electrical, instrumentation and controls (E⁣)works.

You don’t need experience across every discipline. We’re interested in strong estimators who can bring relevant technical and commercial expertise to a multidisciplinary environment and want the chance to broaden their experience.

Working alongside a capable and collaborative team, you’ll combine technical expertise, commercial insight and strategic thinking to develop competitive submissions that support continued business growth.

About McMahon Services

McMahon Services is one of Australia’s largest privately owned construction, industrial and environmental services organisations, employing more than 1,300 people across Australia.

Our Engineering & Projects team delivers complex, multidisciplinary work across some of Australia’s most critical industries. We invest in our people, support long-term careers and provide genuine opportunities to grow alongside a strong national project pipeline.

Why Adelaide?

Thinking about your next career move? Adelaide offers the opportunity to take on challenging, high-profile work while enjoying everything that comes with living in South Australia.

The city has a packed calendar of major events, including Gather Round, the Tour Down Under and Adelaide Fringe, while some of Australia’s best food and wine regions are right on your doorstep.

Spend your weekends exploring the Barossa Valley and McLaren Vale, head to Hahndorf and the Adelaide Hills for great food, craft beer, wineries and distilleries, or make the most of Adelaide’s beaches, restaurants and outdoor lifestyle.

With so much within easy reach of the city, Adelaide offers a outstanding balance between building your career and having time to enjoy life outside of work.

If you’re currently based interstate and considering making South Australia home, relocation assistance can be discussed for suitable applicants.

About the Role

As Senior Estimator,



you’ll lead estimating activities across a range of complex Engineering & Projects opportunities.

You’ll work closely with estimators, engineers, operational teams, subcontractors and suppliers to develop robust cost estimates, practical methodologies and competitive commercial strategies across multidisciplinary scopes.

Your background might be in SMP, mechanical, electrical, industrial construction or broader infrastructure estimating. What matters is your ability to understand complex scopes, develop accurate estimates and bring together the technical and commercial inputs needed to build a strong tender.

This is a role where your expertise will directly influence tender strategy, project outcomes and future work across the business.

Additionally, we work on numerous ECI style contracts, so experience in running an ECI of a technical nature, would be of high value

What You’ll Do

- Lead the preparation and delivery of detailed cost estimates.
- Develop first-principles estimates using internal and subcontractor inputs.
- Estimate multidisciplinary packages, including SMP, mechanical, electrical and associated construction works.
- Manage tender submissions, EOIs and post-tender activities.
- Coordinate estimators, engineers and submissions teams.
- Develop construction methodologies, programmes and cost strategies.
- Identify and manage commercial and technical risks and opportunities.
- Engage with subcontractors and suppliers to obtain competitive pricing.
- Support tender negotiations and successful handover to project delivery teams.

What You’ll Bring

- 7–10+ years’ experience in construction or engineering estimating.
- Experience delivering medium to large multidisciplinary tenders.
- Estimating experience across SMP, mechanical, electrical, industrial or major infrastructure projects will be highly regarded.
- Strong commercial acumen and understanding of project cost structures.
- Proven ability to work effectively with technical, operational and commercial stakeholders.
- Strong communication, negotiation and problem-solving skills.
- Tertiary qualification in Engineering, Construction,



Quantity Surveying or a related discipline highly regarded.

What Will Set You Apart

- Experience across Water, Industrial, Resources, Energy, Defence or Oil & Gas environments.
- Strong SMP, mechanical and/or electrical estimating knowledge.
- Understanding of D&C;, ECI and construct-only delivery models.
- Strong first-principles estimating capability.
- Ability to develop innovative and value-engineered solutions.
- Experience contributing to complex tender and project strategies.

Why Join McMahon Services?

- Work on complex, high-value multidisciplinary projects across critical infrastructure and industrial sectors.
- Apply your SMP, mechanical, electrical or construction estimating experience across a broader project portfolio.
- Gain exposure across Water, Defence, Resources, Industrial and Energy opportunities.
- Join a collaborative and high-performing Engineering & Projects team.
- Genuine career progression within a growing national contractor.
- Relocation assistance can be discussed for suitable interstate applicants.
- Enjoy everything Adelaide and South Australia have to offer—from Gather Round, the Tour Down Under and Fringe to renowned wineries, distilleries, food and beaches.
- Access ongoing professional development through the MAC Learning Academy.
- Be part of a business with a strong focus on safety, innovation and continuous improvement.

Ready to Make Adelaide Home?

If you’re an experienced estimator from an SMP, mechanical, electrical, industrial or infrastructure background and you’re ready for greater project variety—and perhaps a lifestyle change—we’d love to hear from you.

Whether you’re already in South Australia or considering a move from Western Australia, Queensland, Victoria or elsewhere in Australia, we encourage you to apply and have a conversation with us.

Relocation assistance can be discussed for suitable applicants.

Apply today and join McMahon Services in Adelaide.

No recruitment agencies please.

At McMahon Services, we embrace diversity and inclusion as fundamental values. We believe that a diverse workforce fosters innovation, creativity and a deeper understanding of the communities we serve. We are committed to creating an inclusive environment where all employees feel valued, respected and empowered to contribute their unique perspectives and talents. We encourage applications from people of all backgrounds, identities and experiences.

📌 Senior Estimator (Perth)
🏢 Mcmahon Services
📍 Perth