This task is one section of Odoo accounting: nine everyday tasks, step by step, with 8 related tasks on one page.
1. Start from the fiscal localization
Go to Accounting → Configuration → Taxes. The fiscal localization creates the rates for your country, and usually activates the main rate only.
Activate the rate you actually charge. Do not type a percentage you have not confirmed. A guessed rate posts the wrong tax.
2. Set the default taxes
Go to Accounting → Configuration → Settings and find Taxes. Set Default Sales Tax and Default Purchase Tax. Odoo applies those to new products.
Choose Tax Included only when your prices already contain tax. Otherwise leave prices tax excluded and let Odoo add the tax.
3. Assign the taxes on the product
Open the product from Accounting → Customers → Products. Set Sales Taxes and Purchase Taxes, then save.
Default taxes do not go back and fill products you created earlier. Open those products and set the fields.
4. Check one draft invoice
Add the product to a draft quotation or customer invoice. Confirm the tax name and amount before you send it. The tax label is what the customer sees on the PDF.
Point of Sale uses the product tax and can replace it with a fiscal position. Map export or special-customer taxes only after the default product tax is right.
5. Frequently asked questions
Which percentage should I create?
Use a tax the fiscal localization already created, or a rate your accountant confirms. Do not guess the percentage.
Why does an older product have no tax?
Default taxes apply to new products. Open the existing product and set Sales Taxes and Purchase Taxes.
Can an export customer use a different tax?
Yes. Fiscal positions can replace the product tax. Set that mapping after the default tax is correct.
6. Related articles and next steps
Menu labels can vary with your Odoo version, installed apps, and permissions.
Odoo documents default taxes and product taxes in the Odoo 19 taxes page.
Continue learning
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