If you want to make a quick one-time tax change for a specific job, click on the "Financial" tab, and then Tax Preferences while inside the job window.
The tax rates saved in the settings section will automatically import to each new job but not to the jobs that have already been made. To change the tax rate in a current job to the one applied in your settings, there is a financial tab on the right which gives you the option to import the tax rate from your personality. Just click this, and it should update to what is currently in your settings.
For more articles related to this topic, click here.