How to delete only the sales bills without changing the quantity in inventory to start a fresh financial year?

Hey there, @inrcycleworld.

Once you delete an invoice, it will automatically adjust your inventory's quantity. 

However, if you want to start fresh, you don't have to delete your invoices. All you have to do enter an inventory quantity adjustment. This way, you can adjust the item's quantity without recording a purchase or sale. Here's how:

1. Click + New and select Inventory Qty Adjustment.
2. Enter the Adjustment Date.
3. In the Inventory adjustment account drop-down, select the appropriate account.
4. Choose the products in the Product field.
5. For each item, enter either a new quantity or a change in quantity.
6. In the Memo field, enter the details about the adjustment.
7. When you're done, click Save and close.

Once done, QuickBooks Online automatically records appropriate adjustments to your stock Asset and Cost of Goods Sold (under stock Shrinkage) accounts.

In case you need to update your inventory quantity adjustment, use this article as your reference: Edit or delete an inventory quantity adjustment.

The Community always has your back, so please let me know if you have any other questions. I'll be more than happy to help. Keep safe.