I need to write off stock that has expired before end of financial year, How do I do this?

We can use the Adjust quantity option to write off the remaining product that has been about to expire, hello236.

To adjust the amount of inventory on hand and reflect any items that may have expired, kindly follow these steps:

1. Navigate to Products & services, and select the specific beauty of the item.
2. Click the dropdown arrow in the Action column and select the Adjust quantity.
3. Enter the Adjustment Date, click the Adjustment reason dropdown, and select Expired.
4. In the Inventory adjustment account drop-down, select the appropriate account.
5. In the New QTY column, enter the quantity of the product you want to remove.
6. Select Save and close.

For more information, please refer to this article: Adjust inventory quantity on hand in QuickBooks Online.

Also, here's an article to assist you in tracking your inventory sales and stock levels in QuickBooks: Use reports to see your sales and inventory status.