Management Accountant B2B SaaS Startup London, HybridThe ClientHarmonic is delighted to be exclusively partnering with a B2B SaaS start-up that has grown their top tier customer base 8x in the last year, with a clear target to double it again by the end of next year. Having closed multiple funding rounds in quick succession, the business is well-capitalised and growing fast, with further investment expected on the horizon.The finance function is intentionally lean: this hire will work directly with the senior finance leader and take on meaningful ownership from day one, with a clear path to accelerating their career in a short period of time.The RoleReporting directly into the VP Finance (who is a strong mentor and committed to investing in this person''s development), the Management Accountant will own core accounting and billing operations across a three-entity structure spanning the UK and multiple US states.Day-to-day, this means preparing consolidated management accounts, overseeing outsourced bookkeeping (UK and US), managing complex usage-based billing reconciliation, and owning AP/AR and compliance processes. The business operates in an AI-first way and welcomes new thinking on process and tooling: this is a role for someone who enjoys building and improving, not just maintaining.Longer-term, there is genuine scope to own the entire finance function as the company continues to scale.Key ResponsibilitiesPrepare and consolidate monthly management accounts across three ..... full job details .....