Head of Finance (Part-Time – 3 Days Per Week)

• Location: Remote (UK)
• Contract: Part-time – 3 days per week (flexible hours/days). Working hours are flexible and can be structured across three full days or spread across four shorter days if preferred.
• Salary: £45k – £60k full time equivalent (pro rated to approximately £27k to £36k depending on experience and working pattern)

Underwaterpistol is an independent Shopify Plus agency built on a simple belief: real impact comes from tight-knit, senior teams who own outcomes end-to-end.

We’ve never tried to become the biggest agency in the room. Instead, we’ve focused on building a team of experienced people who think independently, challenge assumptions, and move quickly when it matters.

Our clients come to us when they want more than a website build. They want a partner who will challenge the brief, bring better ideas, and help them make confident decisions about how their eCommerce should evolve.

Inside the agency, that means we trust people to take ownership of their roles and contribute to the momentum of the business.

We’re now looking for a Head of Finance to bring clarity, structure and commercial insight to the financial side of the agency as we continue to evolve.

This is not a traditional back-office finance role.

You’ll work closely with the Managing Director and leadership team to ensure the agency’s finances are clear, disciplined and commercially aligned with how the business actually runs.

That means owning the financial fundamentals - reporting, cash flow, forecasting — while also helping leadership understand what the numbers are really telling us about the health of the agency.

This role replaces a largely outsourced finance function, bringing financial leadership and operational ownership in house so the agency has clearer financial visibility and stronger day to day financial discipline.

You will also take ownership of building reliable finance processes and reporting rhythms that leadership can trust, reducing the need for leadership to drive finance activity themselves.

We’re looking for someone who is comfortable operating inside a small, senior team, who enjoys working closely with decision-makers, and who takes pride in bringing clarity to complex financial situations.

• Prepare and present monthly management accounts

• Maintain accurate financial records and oversee day-to-day financial operations

• Ensure the agency always has a reliable view of financial performance

• Run a clear monthly reporting rhythm with leadership, including presenting financial performance and identifying key actions.

• Translate financial performance for non finance stakeholders

• Manage cash flow forecasting and visibility, ensuring risks or issues are flagged early.

• Monitor working capital and debtor levels

• Support leadership in maintaining strong financial discipline across the business

• Help leadership understand what the numbers mean, not just what they are

• Support pricing and commercial decisions where needed

• Provide financial modelling and forecasting when required

• Oversee accurate and timely invoicing processes and financial record-keeping

• Monitor project financial performance and agency profitability

• Work closely with operations to improve financial visibility across the delivery lifecycle

• Own credit control, ensuring debtor days remain healthy and overdue invoices are actively managed.

• Oversee payroll processing and ensure employees are paid accurately and on time, whether processed internally or via an external provider.

• Ensure financial compliance and strong financial processes

• Manage VAT returns and relevant filings

• Work with external accountants on year-end accounts and statutory reporting

• Continuous improvement of existing financial processes to support the agency's growth plans

Essential

• Previous experience in a Head of Finance, Finance Manager or Financial Controller role

• Experience working within a digital agency, marketing agency, or professional services business

• Strong understanding of project-based revenue models

• Experience producing management accounts and financial reporting

• Strong cash flow management and forecasting capability

Desirable

• Experience working in a

• Experience working closely with leadership teams

• Familiarity with Xero or similar accounting platforms

• Comfortable leveraging AI tools and large language models (LLMs) to enhance financial reporting, analysis and operational efficiency

You’ll likely enjoy this role if you:

• Prefer working closely with decision-makers rather than sitting in a large finance department

• Take pride in bringing clarity and structure to financial operations

• Are comfortable being hands-on while still thinking commercially

• Enjoy operating inside small, high-trust teams

• Care about the quality and integrity of the numbers

• Have a proactive mindset and enjoy improving systems, processes and financial discipline across a business.

• This role often suits experienced finance professionals looking for a senior role with flexibility, for example those balancing work with family commitments.

• Join a tight-knit senior team where your role genuinely matters

• Flexible part-time structure across three working days

• Opportunity to play a key role in how the agency operates and grows

• A culture built around trust, ownership and momentum

If you're an experienced finance professional who enjoys working closely with leadership and bringing clarity to growing businesses, we'd love to hear from you.