How do i include GST on an invoice

I've got the steps to guide you in adding the information, geoff5.

Let's make sure to set up your GST by following these steps:

1. On the left panel, click GST.
2. Click the Get started button.
3. In the Set up BAS page, select the accounting method for your GST and the often you pay the taxes (Quarterly, Monthly, Annually).
4. Click Save and finish.
5. On the next page, click Maybe later or Connect the ATO.

Once done, we can create the invoice and add the tax. 

Here's how:

1. Click the Plus (+) icon located in the upper right-hand corner.
2. Under Customers, click Invoice.
3. Select the customer's name from the Customer drop-down list. 
4. Choose the Invoice date and from the Amounts are drop-down menu, select if the item is Excluded of tax, Inclusive of tax, or Out-of-Scope of GST.
5. Enter the Product/Service details.
6. Select the tax from the GST column.
7. Click Save and close.

Here's a sample screenshot for your reference.

I'm also adding these articles that will help you lodge the BAS and record the payment in QuickBooks.

• Lodging a BAS
• Recording a GST payment (BAS Payment)

You can always leave a reply if you have additional questions about GST in QuickBooks. Thanks.