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VAT practical manual 2021.

Calculating the taxable base

1. Calculation using the profit margin of each operation

The tax base is the profit margin, excluding VAT .

Profit margin:

(Sales price, VAT included - Purchase price, VAT included)


An antique reseller buys a piece of furniture for 100 euros (VAT included) and sells it for 200 euros (VAT included).

Profit margin = 200 -100 = 100 (VAT included).

Tax base = 100 ÷ (100 + 21) (1) x 100 = 82.64 euros

Accrued fee = 82.64 x 21% = 17.35 euros


(1) General tax rate. If books were sold, for example, the figure would be 4 not 21, given that book deliveries are taxed at the reduced rate of 4%.

2. Calculation using the global profit margin.

This is applied to certain goods when the taxpayer has chosen to file the declaration to start an activity, or in the month of December in the year before it is set to take effect, and until the time it is waived, which cannot occur until the end of the next calendar year.

Goods to which it applies:

  • Stamps, state-issued paper, notes and coins of philatelic or numismatic interest.

  • Records, magnetic tapes and other audio or image supports.

  • Books, magazines and other publications.

  • Goods authorized by the Tax Management Department of the AEAT upon request of the interested party. The Administration can revoke this authorisation if the circumstances that give rise to it are not present.

The tax base is constituted by the global profit margin for each settlement period minus the VAT quota that corresponds to this margin.

Overall profit margin:

(Sales price, including VAT, of the deliveries of goods in the settlement period - Purchase price, including VAT, of the goods acquired in that same period)

Exempt deliveries for export or similar operation, those related to free zones, free warehouses and other warehouses, nor those related to customs and tax regimes are not taken into account in purchases or sales.

If this margin is negative, the gross tax base will be zero, and the margin will be added to the purchase amount of the following period.

Taxable persons must carry out an annual regularization of their stocks as follows:

Stock regularization

(Ending balance - beginning balance) is:

  • Positive : is added to the sales of the last period
  • Negative : is added to purchases from the last period

For the purposes of this regularization, in cases of initiation or cessation of the application of this modality of determining the tax base , an inventory must be made of the stocks on the date of commencement or termination. cessation, recording the purchase price of the goods or, failing that, the value of the good on the date of its acquisition. These inventories must be submitted within 15 days from the start or cessation. Its presentation can be made at the Delegation or Administration of the AEAT of the tax domicile or electronically through the procedure enabled at the Electronic Headquarters for the presentation of the inventory of stocks for the beginning or cessation of activity subject to special VAT regimes .