Assessing Officer Code mandatory: PAN applicants must supply jurisdictional AO details when submitting Form 49A/49AA. Providing the Assessing Officer (AO) Code is mandatory in Form 49A/49AA; applicants must fill the AO Code comprising Area Code, AO Type, Range Code and AO Number of the jurisdictional Assessing Officer, obtainable from the Income Tax Office, PAN centres, or PAN service provider websites.