I appreciate you running some tests and attaching screenshots, @ks15.
The VAT calculation in QuickBooks depends on the selected preference. However, since the setup is correct and it's still giving you incorrect calculation, I'd recommend contacting our phone or chat team.
They can utilize the screen sharing tool to take a closer look and further investigation on your QBO account. You may refer to the steps provided by my colleague above on how to get their directory.
For future help with VAT, check out the following links:
Keep me updated on how the call went or if you have other questions. I'm just a post away. Have a good one!
