Good dayWe found our invoices not to be in numerical order, jumping from, e.g. the last no being #5160 and the following day starting the first no #5216. Please assist

Hi there, Alex. I’d like to provide you with additional information about why your invoice numbers are not in order.

It's possible that you've deleted some recent invoices in your account. In QuickBooks Online, once the Custom transaction numbers feature is enabled in your settings, it will automatically enter the invoice number from the last invoice created.

I've added a screenshot for your visual reference.

Once you've enabled it, you will have the option to manually add the invoice number in the designated field. Also, you don’t have to worry about the invoice being duplicated, as there will be a prompt message indicating that it's a duplicate.

Furthermore, you may want to check out this article to help make your sales forms look professional: Customise invoices, estimates, and sales receipts in QBO.

Additionally, you can utilize the recurring transaction feature to automatically send your invoices to your customers and avoid the need to send them manually.

If you have any questions or need further assistance, feel free to reach out. Always remember, I'm here to help you 24/7. Take care!