By composition, ECOWAS can be regarded as a

ECOWAS (the Economic Community of West African States) is an intergovernmental organisation established in 1975 by the Treaty of Lagos. By its composition, ECOWAS is classified as a regional organisation because its membership is drawn exclusively from countries within a specific geographic region: West Africa.

International organisations are classified based on their scope of membership:

• A global organisation (such as the United Nations) has membership open to countries from all parts of the world.
• A continental organisation (such as the African Union) encompasses an entire continent.
• A regional organisation covers a specific sub-region within a continent. ECOWAS covers only West Africa, not the whole of Africa.
• A bilateral organisation involves only two countries in a specific agreement, which does not describe ECOWAS with its fifteen member states.

Since ECOWAS is limited to West African states and does not include countries from East, Southern, Central, or North Africa, it is a regional rather than a continental organisation.