Enable tax in purchase bill

Hello there, @kshitij-sinha-ci. 

I appreciate your time to share your concern today. As an insight, the tax on your purchases is paid and filed by your vendor. Hence, you don't need to set it up or add it to your transactions. 

Should you need to track the tax portion, you can add it to your transactions as another item. 

For future reference, check out this link with articles that can help you learn more about managing your bills, expenses, and suppliers in QuickBooks Online. 

Let me know if you have additional questions. I'll be glad to your guide. 

Still, we just to know that is there any way to enable or apply tax on purchase bills? 

Thanks for getting back with the Community, kshitij-sinha-ci.
 

You can track sales tax on purchases by setting up an appropriate account for it, then using it when creating a purchase order or bill.
 

Here's how to track tax as a liability to be paid later:

1. Use your Gear (⚙️) icon, then go to Chart of Accounts.
2. Click New.
3. Choose Other Current Liabilities for its Account Type and Detail Type.
4. Enter a name and any other necessary details.
5. Hit Save and close.
6. In the left navigation bar, press + New and choose Bill or Purchase order.
7. Under your Category column, pick the Other Current Liabilities account.
8. Specify all of the necessary details.
9. Select Save and close.

You can also track sales tax as expenses not to be paid later.
 

I've included a detailed resource about tracking taxes on purchases from vendors which may come in handy moving forward: Track sales tax on purchases from vendors
 

That article is for QuickBooks Desktop, but the same concept applies to QuickBooks Online.
 

Please feel welcome to send a reply if there's any additional questions. Have a great day!