Senior Billing Specialist in Milton Keynes

We exist to create positive change for people and the planet. Join us and make a difference too!

We are hiring for a Senior Billing Specialist to join us permanently on a hybrid working basis from our Milton Keynes office. With this role, you will be accountable for delivering accurate, timely, and compliant customer invoices and credit notes across an assigned billing portfolio, supporting revenue recognition, cash collection, and the client experience.

While the role does not have direct reports, it is expected to set the standard and lead by example, supporting “right-first time” billing through strong personal delivery, proactive issue resolution, and day-to-day guidance to Billing Specialists and peers, working closely with the Team Leader/Billing Manager.

The role collaborates proactively with Sales, Operations/Service Delivery, Contracting, Master Data, Credit & Collections, Cash Application, and Query/Resolution to unblock dependencies, resolve billing queries and disputes, prevent repeat defects, and protect the customer experience. The Senior Billing Specialist supports month-end and year-end activities (cut-offs, backlog management, revenue/AR substantiation support and accrual inputs) and contributes to continuous improvement and ERP/OTC transformation initiatives by embedding standardised ways of working, playbooks and automation-ready processes.

Key Responsibilities

• Deliver accurate and timely invoicing and credit notes across an assigned billing portfolio, ensuring compliance with contractual, tax, and control requirements.
• Own billing performance, meeting agreed KPIs such as invoice timeliness, right-first-time accuracy, backlog reduction, and query resolution.
• Manage complex billing scenarios (e.g. multi-entity, milestone, recurring and consolidated billing) ensuring correct data, approvals, and documentation.
• Investigate and resolve billing queries and disputes, working cross-functionally to identify root causes and prevent repeat issues.
• Partner with Sales, Operations, and Finance teams to unblock billing dependencies, improve cash flow, and enhance customer experience.
• Support month-end and year-end activities, including cut-offs, accruals, and audit documentation to ensure accurate revenue reporting.
• Maintain strong financial controls, ensuring billing accuracy, audit readiness, and compliance with internal policies and external regulations.
• Act as a subject matter expert, providing guidance to peers, driving continuous improvement, and supporting process standardisation and automation initiatives.

To be successful in the role, you will have

• Proven experience in a senior billing role, ideally within a global or shared services environment, handling complex billing processes.
• Strong understanding of contract-to-billing processes, financial controls, and relevant tax regulations (e.g. VAT/GST).
• Demonstrated ability to deliver against KPIs and performance targets, with a focus on accuracy and efficiency.
• Excellent stakeholder management skills, with the ability to collaborate effectively across Sales, Finance, and Operations teams.
• Solid analytical skills and attention to detail, with strong Excel capabilities (e.g. pivots and formulas).
• Experience working with financial systems (e.g. SAP or similar ERP platforms) and multi-currency environments.
• A proactive, resilient and customer-focused mindset, with the ability to prioritise workload and deliver under pressure.

Grow your career and expand your skills and knowledge. At BSI, we offer opportunities to work across industries and across the globe. You’ll benefit from the different perspectives and experiences of your international colleagues, as well as ongoing training and development.

Salary Range: £31,450 - £35,000. The advertised salary range reflects the level, scope and responsibilities of the role. Starting salary within that range will be determined based on experience, skills, market considerations and alignment with internal equity principles.

We offer flexible working, as well as 27-days annual leave, paid sick leave, bank holidays, health insurance, life insurance, pension plan with company contribution, car allowance (dependent on role), income protection, paid maternity leave, paid paternity leave, paid parental leave, adoption leave, compassionate leave, paid bereavement leave, learning and development opportunities, and a wide range of flexible benefits that you can tailor to suit your lifestyle.

Together, we are building an organisation that is ready to meet the challenges ahead. Grow your career as you help us shape what comes next.

We exist to have a positive impact. Our people influence international thinking and action on important issues. Our 86,000 customers are based in 193 countries across the globe.

We’re focused on our future – and we’re looking for people who want to grow with us as we take on the challenges of tomorrow. At BSI, you’ll find a workplace where everyone can flourish and thrive, where innovation is encouraged and where learning is part of your everyday. You’ll contribute to work that shapes industries and enhances lives – and you’ll take pride in what you do.

We’re looking for passionate people who want to make a difference in a purpose-led organisation. If that sounds like you, apply now. Together, we can help create a better society and a more sustainable world.

D&I Policy

BSI is committed to ensuring the diversity of our workforce reflects that of our clients and the communities in which we operate. Our goal is to create a sense of belonging for all employees by providing opportunities to develop, grow, and engage with our global organization all while having fun doing great work. BSI is a community where everyone can thrive.

If you require any reasonable accommodations to be made on account of a disability or impairment throughout our recruiting process, please inform your Talent Acquisition Partner.