Hello bwilliams-concho!
Yes, you can change the date on a check. Let me help you.
Let's find the transaction first so we can edit it. You can go to the Accounting menu, Chart of Accounts, then click the View register of the affected account. Look for the transaction and select it to expand the view. Change the date under the Date column, then save it.
When you select the transaction, you can also click the Edit button so you can make changes. Once done, simply click Save and close.
Also, I added this article if you need help in preparing for a new fiscal year: Year-end guide for QuickBooks Online.
Shoot me a reply if you have other concerns. Take care!
