According to the IRS instructions for audit notices (Publication 3498-A for individuals, Publication 5182 for businesses), you generally have 30 days to respond and provide requested documents. However, the specific response deadline will be stated in your audit notice. It’s crucial to meet this deadline or request an extension if needed, as failing to respond can lead to the IRS making adjustments based on available information. Consult the notice carefully and don’t hesitate to ask the auditor for clarification if the deadline is unclear.