The usability of customer facing software interfaces is a source of competitive advantage for organisations. The usability of systems has also shown to encourage the effective and efficient completion of tasks and in consequence, operations. Furthermore, competitive analysis of the usability of software products has been shown to be a useful tool in the adoption of the user centred design philosophy within organisations. However, low adoption of usability evaluation is prevalent due to a lack of methodologies to support organisations in their endeavours to achieve better usability. Therefore, the purpose of this study is to present a methodology to compare the usability of information systems. By using such a methodology, organisations will be able to gauge the standard of the usability of their information systems, by comparing it to others.