Omnichannel retailing has revolutionized the retail industry by enabling seamless customer experiences across multiple sales channels. However, managing inventory allocation and purchase order massification within SAP systems remains a significant challenge. This paper explores strategies for optimizing inventory allocation and scaling purchase order massification within SAP, leveraging advanced functionalities and automation. The study highlights the benefits of integrating SAP modules, artificial intelligence (AI), and machine learning (ML) to enhance efficiency. By addressing challenges and limitations, the paper provides recommendations for future improvements and strategic adoption in the evolving retail landscape.