Senior Commercial Manager IPTP

Shape Britain’s Energy Future with Sizewell C

Location:

London, Suffolk, Bristol
Contract Type:
Permanent - Office-based with hybrid flexibility (typically 2–3 days per week)
Working Pattern:
Full time
Closing Date:
Friday 9th January 2026

Why Join Us?

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 chance to lead at scale and play a pivotal role in Britain’s journey to energy security and Net Zero.

Senior Commercial Manager

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 Do

• Lead the commercial management of major programmes within heavy civils or large-scale engineering and infrastructure projects.

• Manage and administer NEC3 and NEC4 Engineering and Construction Contracts, ensuring compliance with contract conditions and effective delivery.

• Prepare and maintain key NEC documentation, including early warning notices, compensation events and programme submissions.

• Draft position papers, prepare commercial reports and author change events to support project decisions.

• Apply your understanding of construction technology, cost drivers and supply chain management to optimise outcomes.

• Mentor and develop junior team members, building capability across the commercial function.

• Engage confidently with senior stakeholders and clients, providing clear advice and updates.

• Take ownership of challenges and deliver solutions from start to finish without the need for direction.

• Contribute to strategic commercial planning and decision-making to support project success.

What You’ll Bring

• Proven experience in major projects and NEC3/4 or FIDIC contracts

• Strong commercial, negotiation, and stakeholder management skills

• Knowledge of UK contract law and procurement best practices

• Degree or equivalent experience

• Professional membership (RICS, CICES, IOB, CIPS) desirable

What’s in It for You

• Salary:
  Competitive salary (depending on experience)

• Bonus: 5% annual target

• Holiday: 28 days + bank holidays

• Pension:
  Market-leading (up to 7.5% employee / 15% employer)

• Benefits:
  Health cover, cycle-to-work scheme, discounts & more

• Hybrid working & ongoing professional development

Key Competencies 

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 now and be part of something extraordinary!

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