Group Reporting Accountant - OneStream Implementation

Report & Consolidation Accountant (OneStream Implementation) | 6-month contract | up to £600 (outside IR35)

Altum Consulting are partnering with a high-growth, international business to recruit a Group Accountant confident supporting the OneStream system implementation.

The Role

You will play a key role in the design and delivery of a new group consolidation and reporting framework, ensuring that financial processes, controls, and structures are effectively embedded into OneStream.

Working closely with finance, IT, and external implementation partners, you will help shape a scalable, high-quality reporting environment across the group.

Key Responsibilities

Financial Consolidation & Reporting

• Support the design and configuration of group consolidation processes within OneStream

• Define and enhance statutory and management reporting outputs
• Validate consolidation logic, including intercompany eliminations, FX, and ownership structures
• Build and refine standardised financial statements, dashboards, and KPI reporting

Systems Implementation (OneStream)

• Translate finance requirements into system design in collaboration with stakeholders and implementation partners
• Contribute to data integration, chart of accounts alignment, and metadata structures
• Support testing cycles (SIT/UAT), including test design, execution, and issue resolution
• Assist in developing calculation rules, workflows, and reporting logic

Data & Governance

• Ensure accuracy and integrity of financial data across entities
• Support the development of governance frameworks for master data and reporting hierarchies
• Document processes, controls, and system configurations

Change & Stakeholder Engagement

• Support the transition from legacy systems to OneStream
• Deliver training and act as a key point of contact for finance users
• Act as a subject matter expert on consolidation and reporting throughout the programme

About You

• Qualified (or close to) ACA / ACCA / CIMA
• Strong grounding in group consolidation and financial reporting (IFRS or similar)
• Experience with EPM / consolidation tools (OneStream preferred; HFM, SAP BPC, Tagetik also relevant)
• Comfortable working across finance and technology teams
• Strong analytical mindset with high attention to detail

If this is something of interest, please reach out to Anya Keinzley on the attached details.