While both MRP and ERP systems offer scalability, ERP systems are generally more scalable due to their modular nature. Businesses can start with core modules and add functionalities as needed, allowing the system to grow with the business. MRP systems, while scalable within the manufacturing domain, may require additional software to manage other business areas as the company expands. For businesses planning for long-term growth, an ERP system provides a more scalable solution that can adapt to changing needs.