How to change transaction numbers like invoice number sequence

Transaction reference numbers help you easily identify transactions. QBO will automatically assign transaction numbers in sequence. But if you want to change the starting custom transaction number of your own, you can do so. You would want to turn the company settings ON once, assign a custom number and turn it OFF again so that QBO can identify number sequence based on the last transaction number.

A separate number sequence appears on:

Invoices, sales receipts, refund receipts, and credit memos
Delayed charges and Delayed credits
Estimates
Purchase orders

For Statements, QBO will automatically control the numbers that reference identify so you can’t change it.

QBO lets you customize your transaction numbers.

How do custom transaction numbers work?
When you turn ON custom transaction numbers:

You can change transaction numbers when you create or modify a transaction.
Transaction numbers can include letters (such as 2017-1001).
New transactions get new numbers (such as 2017-1002), based on the last transaction. You’ll be warned if you try to enter a duplicate transaction number.

When you turn OFF custom transaction numbers:

Transaction numbers are never changeable, even numbers created with custom transaction numbers on.
Transaction numbers are assigned when transactions are created.
Transaction numbers are sequential, based on the last number, starting at 1.

To turn custom transaction numbers ON or OFF from the company settings:

Click the Gear icon at the upper right corner > Your Company > Account and Settings).

For customer transaction numbers on sales forms:

Click “Sales” on the left, and then click the edit icon for “Sales form content”. Select the “Custom transaction numbers” checkbox, and click Save.

For custom numbers on purchase orders:

Click Expenses on the left, and then click the edit icon for Purchase orders. Click the “Use purchase orders” checkbox. Select the “Custom transaction numbers” checkbox, and click Save.