The current surcharge rates are 5.2% for goods taxed at 21% VAT, 1.4% for goods at 10%, 0.5% for goods at 4% and 1.75% for tobacco (article 161 of the Spanish VAT law). Companies (SL) are outside this scheme, and if you are the one selling to a retailer under it, you as the supplier must invoice the surcharge and pay it over.
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