Since its reform in 1999, no political party commands an overall majority in the House of Lords. The chamber appears to feel more confident, and government defeats there are common. Earlier studies have shown why the government faces defeats in the Lords, concluding that it is usually the Liberal Democrats that hold the balance of power. Here we analyse the lasting policy impact of Lords defeats. We find that far from being routinely reversed in the House of Commons, many Lords defeats are substantially accepted. Furthermore, many of these are on key policy issues. We also examine which factors are associated with a Lords ‘win’ on legislation, finding that obvious factors such as the size of the majority against the government are not significant. We conclude that the Lords is an important policy actor and should be taken more seriously, but that its ability to make policy gains remains unpredictable.