This study examines the association between tax avoidance and ex ante cost of equity capital. Based on prior research, we develop two proxies for investors’ expectations of tax avoidance and explore whether deviations from those expectations result in higher ex ante cost of equity capital. We find that the ex ante cost of equity capital increases with tax avoidance that is either below or above investor expectations and that the increase is larger for tax avoidance that exceeds investors’ expectations. We then examine whether firms that alter their future tax avoidance exhibit a lowering of their ex ante cost of equity capital and find that tax avoidance decreases (increases) from the prior year for firms that were above (below) investors’ expectations in the prior year. These results are consistent with the trade‐off suggested by the Scholes and Wolfson framework and reinforce the notion that balancing tax benefits and non‐tax costs is an important feature of firms’ tax planning.