We propose a new method to estimate a repeat-sales house price index. Our unbalanced panel method employs an OLS panel regression to estimate the (log) house price as a function of time fixed effects and house-specific fixed effects. Comparisons are made across three repeat-sales methods using actual data, and using simulated data with both stationary and non-stationary relative price innovations. The unbalanced panel method comprehensively utilises all sale information on a house rather than splitting sales into distinct pairs. It is the simplest of the methods to implement, and possesses superior properties to the other two methods under a wide range of data generation processes.