12-Month ContractLondon (Hybrid 2/3 days in the office a week)We''re looking for a Senior Investment Accountant to join a UK life insurance business undergoing an exciting post-acquisition US GAAP accounting transition. This is a hands-on, technical role, reporting into the Head of Investment Accounting and Reporting, and working closely with internal stakeholders and external consultants.Responsibilities:Apply your US GAAP investment accounting expertise (ASC 320, EIR, OCI, debt vs loan classification) across a broad investment portfolio.Build structured Excel models for amortised cost, AFS accounting, and month-end reporting.Design and implement interim processes, controls, and future-state operating models for investment accounting.Support parallel reporting, validation, and handover into business-as-usual operations.Work across diverse investments, including corporate bonds, sovereigns, private debt, commercial mortgages, and infrastructure loans.Requirements:Qualified accountant (ACA, ACCA, CIMA) with strong US GAAP investment experience.Big 4 Audit or Accounting Advisory background, ideally Senior/Assistant Manager level.Experience in accounting transitions, acquisitions, or complex change programmes.Advanced Excel skills and ability to build auditable, financial reporting models.Experience in life insurance or complex investment structures is a plus.This is a unique opportunity to play a key role in a high-profile US GAAP transition, shaping processes, controls, and ..... full job details .....