This provision establishes the rules for displaying prices for taxable supplies. The default requirement is that all declared prices must be inclusive of VAT. However, the text permits the declaration of tax-exclusive prices for two specific cases: supplies intended for exportation and supplies made to another VAT-registered person, provided it is explicitly identified as such. The provision mandates the use of tax-exclusive pricing for supplies subject to the reverse charge mechanism under Article 48(1) of the Decree-Law and for certain taxable goods supplied to a registrant as per Article 48(3) of the Decree-Law.