The profound changes that would accompany a No Deal Brexit will transform the legal environment in which business operates, from changing the terms of trade relationships in Europe, to the structure of regulation and the content of laws. This paper explores the consequences for the Rule of Law for Business from these changes, by drawing on the perspectives of experts from the Bingham Centre's business network and other Brexit experts. Our interviews revealed that the search for certainty over the laws on Exit Day has assisted business to make extensive preparations for a No Deal exit. However, it has not provided sufficient information over the future relationship to enable long-term planning. Moreover, the vast swathes of law passed under delegated legislation, and prospect for the UK to track EU rules without democratic input threatens to jeopardise Rule of Law principles certainty, clarity and legitimacy.