Job Description

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Senior Commercial Manager
Sizewell C

Contract Type: Permanent - Office-based with hybrid flexibility (typically 3 days p/w in the office)
Working Pattern: Full time
Closing Date: Sunday 16th August 2026
Location: London
Salary: Circa £78,000 depending on experience
Bonus: 5% annual incentive
Pension: Up to 7.5% employee contribution / 15% employer contribution
Holiday: 28 days plus bank holidays
Benefits: Flexible benefits

Impact:

Sizewell C is one of the UK's most ambitious infrastructure projects—a next-of-a-kind nuclear power station that will deliver clean, reliable energy for generations. Following our Final Investment Decision, construction is fully greenlit. This is your opportunity to play a key role in delivering a nationally significant project that will support Britain's energy security and Net Zero ambitions.

We’re looking for a seasoned commercial professional with extensive experience delivering major programmes, ideally within heavy civils or large-scale engineering and infrastructure projects valued between £10m and £100m+. You’ll bring a deep understanding of construction technology, cost drivers, and supply chain management, combined with strong working knowledge of NEC3/NEC4 contracts—particularly in contract management and administration. Your ability to draft position papers, author change events, evaluate complex quotations, and produce clear commercial reports will set you apart.

What You’ll Doing:

Leading the commercial management of major design programmes within heavy civils or large-scale engineering and infrastructure projects.
Managing and administering NEC3 and NEC4 PSC and bespoke SZC contracts, ensuring compliance with contract conditions and effective delivery.
Preparing and maintaining key commercial documentation, including early warning notices, compensation events and programme submissions.
Drafting position papers, prepare commercial reports and author change events to support project decisions.
Applying your understanding of construction technology, cost drivers and supply chain management to optimise outcomes.
Mentoring and developing Commercial Managers and Assistant Commercial Managers, building capability across the commercial function.
Engaging with senior stakeholders and clients, providing clear advice and updates.
Taking ownership of challenges and deliver solutions from start to finish.
Contributing to strategic commercial planning and decision-making to support project success.

What You’ll Bring

Proven experience in major projects and NEC3/4 contracts
Strong commercial, negotiation, and stakeholder management skills
Knowledge of UK contract law and procurement best practices
Degree or equivalent experience
Professional membership (RICS, ICES, CIOB, CIPS) desirable or working towards chartership.

Why Join Us

A major infrastructure project with national impact 
Hybrid working with flexibility built in 
Competitive salary, bonus and benefits 
Clear progression and development opportunities 
Supportive, collaborative team environment  

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 tier 1s and 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.

For this role you must have evidence of right to work in the UK. As a project, we do not discriminate on the grounds of age, gender, race, colour, religion, disability or sexual orientation, and we welcome applications from all sections of the community.