The disregard regulations are special rules that operate to mitigate potentially adverse corporation tax implications arising from the use of fair value accounting for financial instruments held for hedging purposes. This article summarises the scope and function of the disregard regulations; and explains the nature and timing of certain elections that companies may need to consider. The deadlines for large companies are tight. In particular, new adopters with calendar year-ends will need to consider electing-in by 30 June.