**Introduction** The “most-favored-nation” (MFN) principle is a core element of the World Trade Organization (WTO) because it anchors the multilateral trading system in non-discrimination. By requiring members to extend any trade advantage granted to one partner to all other members, MFN reduces fragmentation, promotes predictability, and underpins the legal and economic coherence of global trade rules[1]. **Functions of MFN in the WTO** **1.** **Non-discrimination as the foundation of multilateralism** MFN is embedded in Article I of the General Agreement on Tariffs and Trade (GATT) and mirrored in Article II of the General Agreement on Trade in Services (GATS)[2][3]. It establishes the obligation that any advantage, favor, privilege, or immunity granted to one member must be accorded immediately and unconditionally to all other members. If a country lowers a tariff for one trading partner, it must apply the same rate to all WTO members, unless a permitted exception applies. This reduces the scope for discriminatory trade blocs and limits the selective use of trade policy. By institutionalizing equal treatment, MFN converts bilateral tariff concessions into multilateral outcomes, ensuring that negotiated liberalization extends across the entire membership[1][2]. **2.** **Predictability and stability in global commerce** MFN enhances certainty for firms and investors by standardizing baseline treatment across markets. When tariff rates and trade advantages cannot be selectively adjusted for specific partners, cross-border commercial planning becomes more stable and transparent[1]. A substantial share of global merchandise trade continues to take place on MFN terms, even amid the expansion of preferential trade agreements[4]. This generalization of treatment reduces transaction costs and supports smaller economies by guaranteeing access conditions equivalent to those enjoyed by larger trading partners. MFN therefore functions as a stabilizing rule within the multilateral trading system[1]. **3.** **Systemic coherence and dispute settlement** MFN reinforces the legal integrity of the WTO framework by establishing a clear, enforceable standard of equal treatment. Because the obligation is explicitly defined in WTO agreements, departures from it can be measured against an objective benchmark and addressed through dispute settlement procedures[2][3]. Absent MFN, the trading system would be driven largely by overlapping preferential arrangements and shifting political alignments, resulting in uneven treatment across partners. Although WTO rules allow specific exceptions — such as regional trade agreements under Article XXIV of GATT and special and differential treatment for developing countries — these exceptions operate within a broader MFN-based architecture rather than displacing it[2][5]. **Conclusion** The MFN principle remains foundational to the WTO because it institutionalizes non-discrimination, amplifies the reach of negotiated concessions, and reinforces systemic coherence. By ensuring that trade advantages are multilateralized rather than selectively distributed, MFN sustains the stability and universality of the rules-based trading system[1][2].
