How do I deal with posting GST collected for invoices from previous year? QB is including it in my 1st quarter when I have already paid this GST in Q4 of previous year.

Hi there, 

I appreciate you reaching out to the Community. Making sure you're recording the transactions the right way is a good exercise for preventing errors in your books. 

I recommend contacting an accounting professional to get more info on this. If you're not in contact with one, I encourage you to search for one on our website using this link here. Doing this will help prevent any future discrepancies. Let me know if you have other questions. I'm here to help.