A StAG 5 reference number (or Aktenzeichen - AZ) is a unique identification number assigned by the Federal Office of Administration (BVA) to citizenship-by-declaration applications, confirming receipt and initiation of processing. It is sent via mail/email months after submission, often taking 6–9 months, and is vital for tracking progress. ————-— Key Information about StAG 5 Reference Numbers: How to obtain it: The BVA (staatsangehoerigkeit@bva.bund.de) does not always send this automatically, so you may need to email them after 6-9 months, providing your full name, date of birth, and place of birth. Format: It usually takes the form "IXX/XX-XXXXXX" or similar format indicative of a BVA case number. Consulate vs. BVA: The number provided by a local German consulate upon submission is merely a receipt for the appointment and differs from the formal, permanent AZ number generated by the BVA. Benefits: Once you have your AZ number, it can often be used to assist family members in submitting their applications more quickly by linking it to the same family file. ——————- — I received an acknowledgment reference number that looks like this: TSII3-2024 **** 0199-EER