Senior Commercial Manager

Sizewell C is entering an exciting phase of growth as we mature into an independent organisation and continue building one of the UK’s largest and most important energy projects. We are now recruiting the below position.

Senior Commercial Manager

Location: London, hybrid basis with travel required.

Contract: Permanent, full-time.

Closing Date: Friday 3rd July 2026

What’s in It for You

• Salary: Circa £82,186 depending on experience
• Bonus: 5% annual incentive
• Pension: Up to 7.5% employee / 15% employer contribution
• Leave: 28 days holiday plus bank holidays

Role Purpose

Reporting To: Commercial Lead – AACF/ Incentivisation/ Performance/ Reporting

The role requires strong collaboration within an alliance environment, combining effective stakeholder engagement with the ability to provide robust commercial challenge in a fast-paced and complex delivery setting.

Responsible for the review and assurance of Annual Actual Cost Forecasts (AACF), alongside the assessment and validation of profit due to Civil WorksAlliance in accordance with Project Alliance Agreement (PAA) incentivisation arrangements, ensuring outcomes are consistent with agreed AACF positions, cost performance, and contractual principles.

The role ensures that forecast cost positions, commercial reporting, and incentive outcomes are accurate, transparent, and aligned with contractual and governance requirements, while driving improvements in data, reporting, and process efficiency.

Key Responsibilities

• Review, challenge, and lead on the agreement of AACF submissions, ensuring forecasts are robust, evidence-based, and aligned with cost, delivery, and risk positions.
• Assess and validate forecast movement and cost trends, ensuring changes are clearly understood and appropriately reflected in the overall commercial position.
• Provide oversight and assurance of PAA commercial performance, including the production and validation of commercial performance reporting.
• Manage and assure profit incentivisation mechanisms, ensuring outputs are consistent with agreed forecasts and contractual principles.
• Provide commercial input on what should be paid based on agreed cost positions, forecast outcomes (AACF), and incentivisation adjustments.
• Ensure alignment across commercial, finance, and project controls data, including contractor submissions and client assurance positions.
• Drive the digitalisation of commercial processes through the use of data, automation, and reporting tools to improve efficiency, accuracy, and insight
• Lead on the governance and audit processes, ensuring outputs are auditable, evidence-based, and compliant with PAA requirements.

Required Skills:

• Effective communication skills, able to present complex commercial and performance information in a concise and structured manner to a range of stakeholders.
• Ability to operate effectively within an alliance, collaborative environment, with a strong “best for project” mindset.
• Comfortable working in a fast-paced, high-pressure programme environment, managing competing priorities and delivering to tight timelines.
• A strong analytical mindset with the ability to interrogate complex cost and performance data, challenge contractor submissions, and provide clear, evidence‑based commercial insight.
• Significant experience in commercial management within major infrastructure or civil engineering programmes.
• Experience in driving improvements in commercial reporting by digitalisation and data quality, including automation of manual processes, standardisation of outputs, and improved traceability.
• Strong capability in Excel at an advanced level to build, review, and manage forecast models, cost reconciliations, incentivisation calculations, and reporting packs.
• Experience using Power BI or similar tools for dashboarding and visualisation, and familiarity with systems such as SAP, CEMAR or Unifier.

Stakeholder Interface

Act as a key interface with the Project Management Office (PMO) team, working collaboratively to ensure commercial performance and reporting are fully aligned with programme controls and governance requirements.

Knowledge, Skills, Qualifications and Experience

• Member of RICS/ICE/CICES/IOB or equivalent professional body.
• Proven ability of working within a complex major project/programme environment in both procurement and post-procurement phases.
• Evidence of successfully undertaking complex procurements and of administering contracts.
• Effective Management and Leadership skills, with clear knowledge of best practice contract methodologies in the UK environment.
• Honed commercial skills and demonstrable ability to make sound decisions on complex matters (considering technical and commercial topics) of high financial value.
• Good understanding of procurement, contract performance measurement, risk management and change and claim management.
• Excellent negotiating, influencing and communication skills.
• Excellent problem-solving skills.
• Experience of working in a dynamic environment with multiple stakeholders.
• Experience of standard forms of contract (NEC and FIDIC) within the power/construction industry on complex major projects/programmes.
• Possesses skills to act as deputy.

Desirable

• Educated to degree level
• Familiar with the nuclear site licence conditions and the nuclear baseline philosophy.
• Understanding of the UK regulatory framework.
• Understanding of UK and international supply chain within the nuclear sector.
• Knowledge of English law and its impact upon the contract and commercial function.

Behavioural Competences

Humility

• Recognise the value brought from different cultures and experiences.
• Be open to other’s points of view and ideas, be willing to debate and to compromise.

Positivity

• Positively challenge poor quality and performance.
• Identify solutions at the lowest possible level.
• Encourage others to bring new ideas forward.

Respect

• Value the rules and environment in which we operate.
• Give and receive feedback with respect.
• Embrace and engage with new people and ideas.

Solidarity

• One team, working closely together and helping each other.
• Empowered teams always looking forward.
• Shared responsibility for delivery the project outcomes.

Clarity

• Communicate clearly and consistently.
• Promote collaboration and team alignment.
• Clearer and faster decision making.
• Drive simplification at all levels.

If this sounds like the next step in your career, we’d love to hear from you. Apply today.