How is the Zakat calculated for a company that manufactures aluminum doors and windows, and does its connection to the annual budget affect the due date for its disbursement if the preparation of the budget is delayed?

You must calculate the cash liquidity and products prepared for trade and pay zakat (definition) on all of them at the end of every Hijri year. It is not permissible to delay zakat after it becomes due. Zakat is calculated by assessing your cash and trade goods at the end of the lunar year, then you pay one-quarter of one-tenth (2.5%). The calculation should be based on the Hijri year, not the Gregorian year. If it is not possible to know the amount on which zakat is due except by preparing a balance sheet, then it must be prepared. If that is not possible, you should pay zakat based on your best estimate of what you believe is due.