What’s the difference between Mainland and Free-Zone licensing for tax?

This drives Magento tax engine + invoicing setup:

• Mainland Trade Licence (issued by DED-Dubai or equivalent), full UAE market access, can sell anywhere in UAE without restriction. 5% VAT applies on B2C + B2B (with TRN reverse charge).
• Free-Zone licence (DMCC, JAFZA, DIFC, ADGM, SHAMS, RAKEZ, etc.), tax holiday on corporate income (originally 50 yr, now affected by 9% federal CT 2023+), but VAT still applies on UAE-mainland sales. Designated Zones (e.g. JAFZA Designated) may be VAT-free for cross-border B2B but mainland B2C still 5%.
• Offshore (JAFZA Offshore, RAK ICC), cannot sell into UAE mainland. Magento store typically used for international export only.

We model this in Magento with:

• Multiple tax classes (mainland B2C 5% / free-zone B2B 0% / export 0%)
• TRN-validated B2B reverse charge invoicing
• FTA-compliant tax invoice format with TRN, supply date, AED amount