Opex Portfolio Controller

• Strong Project Accounting or Project Finance experience within a complex, multi-project environment.
• Experience supporting CAPEX/OPEX governance, investment submissions, budgeting, forecasting, and month-end processes.
• Experience providing financial challenge and insight to senior stakeholders.
• Strong analytical, reporting, and business partnering skills.
• Experience working with Project and Programme Managers and PMO teams.
• Proficiency in Microsoft Excel, PowerPoint, and SharePoint.
• Strong financial analysis and data interpretation skills.
• Working knowledge of SAP, SAC, or similar finance systems.
• Understanding of CAPEX/OPEX accounting and financial controls.
• Familiarity with portfolio-level financial reporting and governance.

• Experience within IT, Digital, or large-scale transformation environments.
• Exposure to resource recharge, cost allocation, or TOTEX models.
• Experience with benefits tracking and value realisation.
• Experience supporting year-end processes.
• CIMA, ACCA, ACA, or equivalent qualification, or working towards one.
• Understanding of capital planning and cost estimation.
• Working knowledge of Earned Value Management (EVM).

Competitive salary up to £65,000 depending on experience

• Competitive salary up to £65,000 per annum, depending on experience.
• Annual Leave - 26 days holiday per year, increasing to 30 with the length of service. (plus bank holidays).
• Performance-related pay plan directly linked to both company and individual performance measures and targets.
• Generous Pension Scheme through AON.
• Access to lots of benefits to help you take care of yourself and your family's health and wellbeing, and your finances - from annual health MOTs and access to physiotherapy and counselling, to Cycle to Work schemes, shopping vouchers and life assurance.

Find out more about our benefits and perks (Please note different T&Cs apply if on secondment)

We are looking for an analytical, commercially focused, and delivery-driven Opex Portfolio Controller to provide financial analysis, governance support, and business partnering across Thames Water's Digital investment portfolio of approximately £100m per annum.

You will support portfolio planning, forecasting, reporting, investment governance, and benefits realisation, providing clear financial insight and constructive challenge to Project and Programme Managers, the Portfolio Finance Manager, PMO, and Digital Leadership Team. You will help ensure robust financial controls, accurate reporting, effective investment decisions, and continuous improvement across the Digital portfolio.

• Lead Opex forecasting, budgeting, reporting, and variance analysis across the Digital portfolio.
• Provide accurate financial inputs for monthly reporting, annual budgeting, and investment reviews.
• Identify financial risks, opportunities, trends, and performance issues.
• Support the preparation, review, and assurance of investment business cases and funding submissions.
• Provide financial guidance, challenge, and insight to Project and Programme Managers.
• Support investment prioritisation and decision-making through clear financial analysis.
• Coordinate portfolio benefits tracking and value realisation reporting for the Digital Leadership Team.
• Produce clear financial and performance reporting, highlighting key risks, opportunities, and actions.
• Support regular finance and portfolio review meetings.
• Ensure compliance with financial policies, accounting standards, CAPEX/OPEX principles, and governance requirements.
• Maintain strong financial controls and support effective portfolio assurance.
• Improve financial reporting, forecasting, processes, tools, and governance practices.

Base location - Hybrid - Clearwater Court, Reading
Working pattern - Full-time, Monday to Friday