Can I setup GST on an existing file or do I need to start a new file

Hi Alison,

Thanks for posting in the Community!

If your client is now GST registered, there is no need to sign up for a new QBO file for the client. You can just enable and set it up the GST and assign GST codes on the transactions moving forward.

As for the previous transactions, they remain on file with out GST codes applied on them. If you need to assign GST codes on them, you will have to manually edit each transaction to apply GST.

Here's how to set up the GST center:

1. Click on the GST tab and click on Get started.
2. Select an Accounting method and the BAS lodgement frequency.
3. Select other tax obligation the client needs to enable in QBO.
4. Click on Save and finish.

That's it! You've set up the BAs and GST and can start assigning GST codes on your transactions moving forward. 

Check this link to learn more about setting up GST in QuickBooks Online.

Feel free to comment  below if you need more information about setitng up the GST in QBO.