Hi there, @doxa.
As much as I would love to advise you on what code you should use, it depends on your products and services. The 0% NR code is for goods and services purchased from non-GST registered suppliers/traders. While the 0% OP code is for the purchase of goods outside the scope of GST.
One of the major benefits of these two different GST codes is that they can make a claim input of GST paid at the time of purchase while computing actual tax liability to be remitted to the authorities. Also, it tells your accounting system whether a transaction includes GST and if yes, what to do with it. You set a default GST code for each account but you can override this at any time for a particular transaction. So an account can include transactions with different GST codes.
As I've mentioned earlier, the descriptions are short and don't go into detail. If you need to know more about these tax codes, it's best to contact the IRAS, as well as consult your accountant to know which tax codes work best for your company.
For additional reference, here are articles that can guide you in setting up GST in QuickBooks Online:
Please leave a reply if you have other QuickBooks-related questions. The Community will be glad to help. Have a great day!
