Amentum is continually expanding our opportunities working on prominent defence projects across air, land and sea supporting the critical capabilities that keep Australia safe. We have a growing presence in cyber, space and nuclear programs. Tell me about this role: We’re looking for an experienced Cost Estimator to join a high-performing team within CASPO, supporting the delivery of complex Defence and international capability programs . In this role, you’ll take the lead on cost modelling, financial forecasting, and analysis , helping shape critical investment decisions across major projects. You’ll work in a highly collaborative, integrated environment while operating with autonomy and influence , partnering with senior stakeholders across Defence and global partners. This is a unique opportunity to contribute to high-impact programs , while growing your expertise in a structured, forward-looking Defence environment . What will I be doing day to day? In this role, your day‑to‑day responsibilities will include: Lead the development of cost estimates, cost models, and forecasting outputs for complex Defence programs Build and maintain forward estimates, financial phasing, and scenario modelling to support program planning Analyse cost drivers, trends, and variances to provide clear, actionable financial insights Provide trusted financial and commercial advice to project teams, senior leaders, and stakeholders Support engineering and project teams with cost inputs for changes, sustainment planning, and capability upgrades Collaborate with international partners and stakeholders on cooperative program cost activities Contribute to procurement activities, including financial analysis of tenders and approvals Ensure alignment with Defence costing frameworks, policies, and governance requirements Drive improvements in cost modelling tools, processes, and reporting capability Build strong working relationships to support high-quality, timely program outcomes What sort of skills do I need? To be successful in this role, you’ll bring: 5–7 years’ experience in cost estimation, financial modelling, or forecasting within Defence, government, or complex project environments Strong understanding of Defence financial management, costing frameworks, and procurement processes Proven experience developing cost models, forecasts, and financial insights for large-scale programs Advanced analytical and problem-solving skills, with the ability to interpret complex data Excellent communication skills, with confidence engaging senior stakeholders and international partners Ability to manage competing priorities and deliver under pressure High attention to detail with a focus on accuracy, governance, and data integrity Australian Citizenship and NV1 Security Clearance essential What’s in it for me? Flexibility - We like our employees to have the flexibility they need to live the lives they choose. Inclusion - Our employees should feel safe bringing their whole self to work, we offer a number of programs promoting inclusion. Benefits and Rewards – Our benefits and rewards includes additional superannuation; flexible leave options; salary continuation insurance; professional certification bonus; employee discount program. Amentum: Trusted Partner in National Security Amentum is a key service provider to the Australian Government, supporting critical national security and Defence capabilities across land, air, maritime, cyber, space, nuclear, and digital domains. With over 880 professionals nationwide, we deliver complex infrastructure, logistics, and technical solutions with a strong focus on quality, safety, and innovation. With 27 years of experience and a presence in major cities and regions, we’re proud of our people—our greatest asset. Join us and be part of a high-performing team with exceptional benefits and career opportunities. Apply directly or reach out to Jeremy Parkinson, jeremy.parkinson@global.amentum.com .
