Study objective: Several studies have reported an association between income inequality and increased mortality, but few have used net income data, controlled for individual income, or evaluated sensitivity to the choice of inequality measure. The study tested the hypotheses that people in regions of Britain with the greatest income inequality would report worse health than those in other regions, after adjusting for individual socioeconomic circumstances. Design: Cross sectional survey. Setting: England, Wales, and Scotland. Participants: 8366 people living in private households Main results: Regional income inequality, measured using the Gini index, was associated with worse self rated health, especially among those with the lowest incomes (adjusted OR 1.55, 95% CI 1.24 to 1.92) (p<0.001). This association was not robust to the choice of income inequality measure, being maximal for the Gini coefficient and weakest when using indices that are more sensitive to income differences among those at the top or bottom of the income distribution. Conclusions: The study found limited evidence of an association between income inequality and worse self rated health in Britain, which was greatest among those with the lowest individual income levels. As regions with the highest income inequality were also the most urban, these findings may be attributable to characteristics of cities rather than income inequality. The variation in this association with the choice of income inequality measure also highlights the difficulty of studying income distributions using summary measures of income inequality.