While turning off sales tax completely isn't available in QuickBooks Online (QBO) once the feature is active, you can set a default option to prevent it from affecting new transactions, Mireille.
This issue commonly arises because certain settings, such as sales tax, automatically transfer when converting from QuickBooks Desktop (QBD) to QBO, even if your business doesn't need them. This likely occurred because sales tax was enabled in your QBD file before migration.
Here's how to change your sales tax in your setting:
- Select the Gear icon.
- Choose Account and settings.
- Select Advanced.
- Click the Accounting section to edit.
- From the Default tax rate selection drop-down, choose the Out of scope of Tax.
- Click Save.
- Then hit Done.

Setting this default prevents you from having to manually select a non-taxable code every time you create a transaction.
If you have any additional questions or need further assistance, feel free to let us know.