What is the tax treatment of goods imported from the UK or from third countries into Gibraltar by traders under the 2026 UK/EU Treaty?

Short answer

Goods from the UK will not have UK VAT/excise applied but will be subject to Gibraltar transaction tax. UK-origin goods (per the TCA) are free from EU customs duties. Non-UK-origin goods transported from the UK will be subject to EU Common External Tariff customs duties, levied at the EU customs post. Collected customs duties are reimbursed to HM Customs Gibraltar minus administrative costs.