The taxes calculated and shown on the Invoices are controlled by the Tax settings in your Shopify admin. Shopify doesn't automate retroactive tax calculations, so if you just finished adding your taxes, there’s no way to adjust taxes for all past orders.

There are situations in which making a tax correction is necessary; however, since tax filing and remitting require direct registration with your local or federal tax authorities, you must consult a tax professional before you make any changes.

You may go through your past orders to identify which ones require adjustment and, depending on the tax rules for your specific jurisdiction, calculate the correct amount of tax that should have been collected at the time of each sale.

Then, to issue updated invoices to your customers, you must do the following:

If you need help with this process, we recommend getting in contact with Shopify to receive complete guidance.
​
Now, if you have to edit many orders or need to make constant adjustments to them, we recommend checking order editing apps such as the Edit Order app by Cleverific. This app allows for easy Tax Adjustments, among other types of edits.