Hi Karen,

There is a new app called TaxAvenger that is an alternative to Avalara/TaxCloud. The main difference is that everything is managed inside of Odoo, other than the tax-rate lookup itself which is handled by a simple API connection. 

The Tax rate info is state/county/city/district specific as the API is address based, not purely zip code based. This means it is just as accurate as Avalara or TaxCloud. Its worth a look as I agree with Ray where he describes how Sales Tax gets complicated very quickly. 
https://apps.odoo.com/apps/modules/18.0/tax_avenger

You should use an outside service:

• Rates can vary not just by state and county, but by city, zip and even special tax districts.  You need the full Street Address.
• The percentages and rules change frequently, requiring constant updates.
• Each state has different rules for what creates a "nexus" (an obligation to collect sales tax). Economic nexus laws mean businesses may owe taxes in states where they have no physical presence. As little as 200 sales a year can obligate you to collect tax in State.
• Some products and services are taxed differently depending on how they are combined in a sale with other products (e.g., adding one item to an order may result in the entire order becoming taxable when it was not before).
• Some states require monthly filings, others quarterly or annually, with different deadlines and reporting formats.
• Incorrect tax collection or remittance can lead to audits, fines, and penalties. 

States aggressively pursue unpaid sales tax.

For all of these reasons we recommend Avalara's Avatax: 

https://www.odoo.com/documentation/master/applications/finance/accounting/taxes/avatax.html

Hi Karen,

What I understand from you is that you are asking about:

1. How to set tax per country per states?
   You can do it by mapping through fiscal position setups in Accounting, check this https://www.odoo.com/documentation/18.0/applications/finance/accounting/taxes/fiscal_positions.html
2. To show sales by country or states, you can do it going to Sales Analysis in Sales App. You can set what fields you want to see
3. If you want to check on the taxes, you can either check the Tax Report in Accounting > Reporting or you can manually do filter in the Journal Items menu.

Hope this helps.