This Practice Note sets out the circumstances in which an extension of time may be granted, upon application of a party, under section 12 of the Arbitration Act 1996 (AA 1996) to a contractual time period for commencing or starting arbitration proceedings under English law. The Practice Note considers the 'reasonable contemplation' test applied by the court under AA 1996, s 12(3)(a), the first basis for an order granting an extension. The Practice Note also considers the second basis for an extension, namely where conduct of one party makes it unjust to hold the other party to the strict terms of the provision in question (AA 1996, s 12(3(b)).