We are working with a London-based organisation that requires an experienced Accounts Receivable Administrator to support the finance team during a busy period. This is a hands-on role suited to someone who can step in quickly and manage AR processes with minimal supervision. This role is paying £150 - £200 a day inside ir35 with hybrid working available. Key Responsibilities High-volume cash allocation within Sage 200 Investigating and resolving unallocated cash and payment discrepancies Maintaining accurate customer ledgers and aged debt reports Liaising with internal teams and customers to resolve payment queries Supporting credit control activities where required Assisting with AR reconciliations and month-end reporting Ensuring strong attention to detail, accuracy and clear audit trails Required Experience Proven experience in an Accounts Receivable / AR Administrator role Hands-on Sage 200 experience is essential Strong cash allocation and reconciliation background Confident working in a fast-paced, high-volume finance environment Good Excel skills Able to work independently and hit the ground running Available to start immediately Desirable Experience in interim or temporary finance roles AAT qualified or equivalent practical experience