Interim Financial Controller | Energy Infrastructure Scale-Up

HarmonicLondonreedpublished 10/01/2026
Must-have:FinTechSeniorLeadHybrid

London / Hybrid

The Client

Harmonic is delighted to be partnering with a fast-growing, fund-backed UK energy infrastructure business. The group delivers critical infrastructure and services to customers across the UK and is playing an active part in the energy transition. With the business scaling quickly and becoming more complex, finance has a central role to play in supporting the next stage of growth.

The Role

Reporting into the CFO, the Interim Financial Controller will lead the Financial Reporting & Control and Operational Finance team of four (two direct reports, two indirect) for an initial three to four months while a permanent appointment is made. This is a hands-on leadership role suited to a steady, experienced pair of hands. The team is capable and knows its systems, so the priority is to take day-to-day management off the CFO, keep the monthly reporting cycle on track and support the team through the upcoming audit. Much of the focus will sit on financial operations: procure-to-pay, purchase orders, weekly payment runs, invoice processing and approvals, and cash in and out of the business. You will be the go-to person for a team handling a high volume of transactions, giving clear guidance on the questions and unexpected issues that come up every day. The brief is to land quickly, earn the team's trust and keep the function running smoothly, rather than to drive wholesale change.

Key Responsibilities

Line manage and support a team of four across financial reporting and operational finance, acting as the first point of call for day-to-day questions and issues. Oversee the monthly accounting and reporting cycle across multiple service lines and the group holding company, reviewing the team's outputs. Lead the procure-to-pay cycle, including purchase order controls, invoice processing and approval, and weekly payment runs. Oversee accounts payable and accounts receivable, keeping controls tight across a high volume of transactions. Manage cash flow in and out of the business, supporting monthly cash forecasting and giving the CFO clear visibility. Provide oversight of the audit alongside the CFO, working with a team that will deliver the detail. Partner with the CFO to keep the finance function steady and well supported through the handover to a permanent Financial Controller.

Essential Experience

Qualified accountant (ACA / ACCA / CIMA). Proven experience as a Financial Controller or in a similar senior finance role, leading and supporting a finance team. Strong financial operations background across procure-to-pay, payments, AP / AR and cash management in a high-volume transactional environment. Experience overseeing the month-end reporting cycle and audit processes. Able to hit the ground running and lead in a supportive, light-touch way over a short assignment. Available immediately or at short notice.

Desirable Experience

Experience in the UK power, energy or utilities sector, ideally within electricity networks or grid connections. Experience in a multi-entity group with several service lines. Familiarity with Xero, e-procurement / purchase order systems and Pleo.

Day Rate: £475-£550 per day (IR35 TBC) Location: London, hybrid (2-3 days a week in the office) Duration: Three to four months Start Date: ASAP

Please feel free to get in touch with Ewan Fenley for more information () Please feel free to share this with any friends or colleagues that may be interested. At Harmonic, we are dedicated to fostering an inclusive and equitable workplace. We actively welcome applications from individuals of all backgrounds and assure you that every candidate will be thoughtfully considered for the roles we represent, without regard to race, religion, gender expression, disability, or sexual orientation.