Can I file a GST return from prior years? does QBO let you go back? GST have never been filed in program yet?

Hi there, 

Welcome to the Community. I'd be happy to assist you filing a GST return in QuickBooks. 

The good thing is you can file as far back as you'd like and I'll guide you through the steps. Here's a helpful article from our Community which will show you how you can do that:

https://quickbooks.intuit.com/community/Sales-tax/File-sales-tax/m-p/261654

When recording the tax filing, you can select a previous date. I encourage you to go through the article and let me know if you've got questions. I'm here to help. :)