Payroll Specialist

Arqit is a global pioneer in post-quantum cryptography: we provide a proven defence against both current cyber dangers and impending quantum threats. Our global team describe Arqit as providing a positive, inclusive and high-performing working environment, where employees feel that managers care about the success and well-being of their teams, individuals feel valued as employees and teams achieve more than they thought possible, together.

There has never been a more exciting time to join Arqit. We are scaling our Finance Operations Centre in Belfast, building a world-class team to support the Group’s continued growth. The finance team is pivotal to the business, ensuring financial information is timely, accurate, complete and compliant with relevant accounting and taxation principles. We have a culture that gives you the opportunity to innovate, take ownership, and scale new heights in your career as the company grows.

We are looking for a detail-oriented Payroll & HR Finance Specialist to manage payroll operations for approximately 110 staff across the UK and US. This role also covers RSU vesting and tax reporting, T&E management and expense policy compliance, forming an important bridge between Finance and HR. The role is based in our Belfast city centre office, with flexibility for hybrid working.

What you’ll be doing

Manage the UK and US payroll processes for approximately 110 employees, providing monthly variance analysis and approvals

Oversee RSU vesting cycles and associated tax withholding and reporting (P11D, W-2)

Manage and reconcile the T&E platform for approximately 150 transactions per month, ensuring compliance with the Group expense policy

Maintain and update the Group expense policy, communicating changes across the business

Oversee pension reporting and ensure timely remittances

Manage all payroll compliance and reporting for the relevant payrolls

Support the statutory reporting cycle by providing payroll schedules and reconciliations

Partner with HR on headcount reporting and budget variance analysis

What we’re looking for

We would expect candidates for this role to meet most or all of the following criteria:

Demonstrable payroll experience, ideally covering both UK and US payrolls

Familiarity with RSU / share scheme administration and related tax reporting obligations

Strong Excel skills and experience with payroll or HRIS platforms

High attention to detail with a commitment to payroll accuracy and confidentiality

Part-qualified accountant (desirable but not essential)

Please note, the ability to work in the UK without visa restrictions is ESSENTIAL.