A whole farm budget for a representative farm in the Lower Namoi Valley in northern NSW was used to analyse the financial implications of a comparative rotational experiment of four cotton-based rotations conducted in recent years at the Australian Cotton Research Institute, near Narrabri. The model was used to compare the rotations, which highlighted the importance of crop selection for the financial performance of the business. Apart from providing a broad brush picture of financial performance, the model also had a stochastic component which was used to analyse the effect of variable commodity prices on the whole farm profitability of each rotation. Mean results indicated a positive return for all rotations within the representative farm budgets for the Lower Namoi Valley, indicating that given restricted irrigation water availability and average commodity prices, each rotation would ensure that the business returned a profit. The rotations varied in resilience to commodity price variability from 74% to 99.5% probability to return a positive farm operating surplus.