We provide the plugin VAT. Change / Reduction in our Community Store, which you can use to make the necessary adjustments for the VAT change. This can be found here.
If you want to make the adjustments manually, this tutorial will explain what you should consider when changing the VAT rate.
Whenever you make changes in this area, we generally recommend that you first create a backup of the database! This provides you the possibility to return to the current status at any time.
In the basic settings under Items > Other VAT rates you can define your own VAT rates for vouchers and discounts.
In the order overview, the name of the selected tax rate is displayed in the column Taxes on the tab Items.
If you change the name of the tax rate, the name of the tax rate as it is now called will also be displayed in older orders under Taxes. (For example 16%)
IIn this example the tax rate with TaxID 2 is deposited for all articles, which use the tax rate with TaxID 1. You can find the exact TaxID in the database table: s_core_tax.
UPDATE `s_articles` SET s_articles.`taxID` = '2' WHERE `s_articles`.taxID='1';
If you have stored fixed tax rates in a shipping method or in a voucher, you should also replace them with the new tax rate.
Additionally, you should check your plug-ins to see if they use the default tax rate. If necessary adjust the tax rate here as well.
Since the gross price remains the same here, the net price is changed here. If you have customer groups for whom the net price is displayed in the front end, this price changes accordingly.
If you have stored tax rules for other countries in your standard tax rate, you should note that these rules refer to the net price of the items. If you have set up a tax rule of 20% for Austria, these will be calculated on the changed net price. The gross price for Austria will then change in your shop.
UPDATE s_articles_prices SET price = price/1.new_tax_rate*1.old_tax_rate
UPDATE s_articles_prices SET price = price/1.16*1.19
This query is reversed for the increase of the tax rate from 16% to 19%:
UPDATE s_articles_prices SET price = price/1.19*1.16
In this example the tax rate is changed from 19% to 16%. This happens for all articles that use the tax rate with TaxID 3. The exact TaxID can be found in the database table: s_core_tax.
UPDATE s_articles_prices, s_articles SET s_articles_prices.price = s_articles_prices.price/1.16*1.19 WHERE (`s_articles`.id = `s_articles_prices`.articleID AND `s_articles`.taxID='3')
UPDATE s_articles_prices, s_articles SET s_articles_prices.price = s_articles_prices.price/1.16*1.19 WHERE (`s_articles`.id = `s_articles_prices`.articleID AND `s_articles_prices`.pricegroup='EK')