How do I fix my sales tax that is not calculated on my Markup, even though I have ticked it as taxable! I have tried everything, but it seems to be a system glidge

I know how critical accurate sales tax calculations are to your operations, and I appreciate your proactive approach to addressing this. Let me take it from here and assist you further in resolving it.
 
To better assist you, could you provide the steps you've already taken to resolve it? Additionally, have you encountered any error messages or prompts? This information will be invaluable in effectively diagnosing the problem and determining if there are any ongoing investigations on our end. 
 
If you haven't tried accessing your account through an incognito window, let's perform this troubleshooting to rule out the possibility of a webpage issue. Numerous cached files in your browser can sometimes cause unusual behavior in your QBO.

You can refer to these shortcut keys below to open an incognito window in all supported browsers:

Mozilla Firefox: CTRL + Shift + P

Microsoft Edge: CTRL + Shift + N

Google Chrome: CTRL + Shift + N

Safari: Command + Shift + N

After starting a new private browsing session, please log into your QBO account and check if it works. If yes, proceed to clear your browser's cache to help the program run smoothly and eliminate technical issues. You can also use other devices and supported browsers as alternatives.

Furthermore, I've included these guide articles that explain how QuickBooks Online automatically determines sales tax rates and how to manually adjust tax calculations when necessary, helping you better understand sales tax management in the platform:

• Learn How QuickBooks Online Calculates Sales Tax
• Override Sales Tax on Transactions in QuickBooks Online

Consider this thread a reliable resource for any sales tax inquiries or concerns. Please keep us updated on your progress by replying below. My team and I are committed to supporting your business needs and ensuring a seamless sales tax processing experience.

My sales tax on my Markup line is still not working. I have cleared my cache. It does not calculate on that line at all?

I truly value the efforts you've put in. Accurate sales tax calculations are vital to businesses like yours and I want to help you achieve that.

Since you already confirmed that you've enabled it as taxable but still sales tax on your markup isn't calculated, let's override the amount to compute it correctly:

1. Open the sales form where the markup is listed.
2. Adjust the Status and Date if necessary.
3. Click on the See the math option.
   
   
   
   
4. Select Override this amount and click on Edit.
5. Enter the correct Rate and Amount correctly.
6. Choose the Reason for override, then click Apply override.
   
   
   
   
7. Once done, click Close.

For more information about overriding sales tax on transactions, please refer to this article: Override the sales tax amount.

If the issue persists, I suggest contacting our support team for additional assistance. They are fully equipped with advanced tools to carry out a comprehensive investigation of the problem and effectively handle the situation at hand.

Here's how to contact them within QBO:

1. Sign in to your QBO account.
2. Go to the Help icon on the upper right part of the page.
3. Select the Search tab and click on the Contact Us button.
4. Select a topic to connect with the appropriate expert.
5. Choose how to connect with our support:

• Via Callback, where they save you a spot and call you back
• Via Chat, to start a chatting session with our support

To find out the available hours when our support team is available to assist you, please see this reference: Get help with QuickBooks products and services.

I'll provide you with this comprehensive guide, which offers an in-depth examination of the taxes you are responsible for, along with clear explanations of the reasons behind those obligations: Learn how to use the Sales Tax Liability report in QBO.

Your attention to detail is thoroughly appreciated and your financial queries are our priority. If questions arise in managing sales forms, I'll be around to offer my support.