Tax Manager

Reporting to
:
Head of Tax / Managing Director

Salary
: £45,000 to £60,000, depending on experience and qualification level

Location
:
Remote - UK

The UK tech sector is growing rapidly and becoming an increasingly important part of the economy. At Onside, we’ve built a genuinely differentiated way to support tech-led businesses, combining premium client service with modern systems, automation and commercial thinking.

We believe the strongest professional services firms of the future will be technology-led by design, with automation and data removing low-value work so people can focus on judgement, relationships and impact. Onside is being built deliberately around that belief. We are not just users of technology; we are, in part, a technology company ourselves, backed by Multiplier, a San Francisco-based, AI-native professional services company designed to transform our industry.

As Growth Tax Manager, you will take ownership of Onside’s wider tax offering for fast-growing, VC-backed technology businesses, acting as a trusted lead on day-to-day delivery while working closely with the Head of Tax and Managing Director.

The role covers the tax matters that become increasingly important as technology companies scale, including transfer pricing, EMI, EIS/SEIS, VAT and wider corporate tax advisory work. You will work directly with founders, senior stakeholders and finance teams, providing clear, practical and commercially useful advice that helps clients make better decisions as they grow.

This is a fast-paced role with high standards. We value accuracy, curiosity and ownership, and there is a clear progression path for people who demonstrate energy, capability and strong commercial judgement. It is an opportunity to help shape a modern, technology-led tax function, work with ambitious clients, and build a strong platform for your continued career.

Applicants must be confident managing priorities, delivering work independently and collaborating effectively in a remote environment, including throughout their initial training and induction period.

This role requires substantial experience of long-term homeworking within a UK accounting practice. Remote working experience gained solely during Covid-19 restrictions will not be considered. Applicants from formal hybrid arrangements may be considered, provided homeworking was a long-term, contracted arrangement involving typically two to three days per week working from home.

• Taking ownership of a portfolio of tax work for start-up and scale-up clients, acting as the key point of contact on the matters they lead.
• Preparing and delivering tax advice on transfer pricing matters, including scoping, technical analysis, report writing and implementation support.
• Preparing EMI valuation reports and supporting clients with EMI and ERS advice and compliance, including HMRC submissions and related advisory work.
• Preparing EIS1 and SEIS1 compliance filings and supporting advance assurance applications.
• Advising clients on VAT matters, including UK and cross-border issues arising as businesses grow and expand into other jurisdictions.
• Supporting clients with ad hoc tax advisory projects, including restructurings, remuneration planning, employment-related tax issues and wider corporate tax matters.
• Reviewing Corporation Tax returns and associated computations on an ad hoc basis, working alongside the accounts team who manage preparation, and providing technical input to ensure accuracy, identify risks and highlight planning opportunities.
• Undertaking tax research, reviewing legislation and HMRC guidance, and forming well-reasoned conclusions based on independent analysis.
• Producing high-quality written advice, reports and technical correspondence for clients and internal use.
• Leading and contributing to client calls and meetings, explaining technical tax issues in a clear, practical and commercial way.
• Building strong client relationships, supporting efficient delivery, and identifying improvements in processes, technology, automation and wider commercial opportunities across the tax function.
• Contributing to the continued development of Onside’s tax offering,…