Swahili is spoken in several countries across East Africa and beyond, with the largest concentrations in Tanzania, Kenya, Uganda, and the Democratic Republic of Congo. It also has official or national status in these areas and is widely used as a lingua franca in the region. Key places where Swahili is spoken:

• Tanzania and Kenya: official or national language status and widespread use in education, media, and government.
• Uganda: many speakers, especially in urban centers and along commercial corridors.
• Democratic Republic of the Congo: prominent in eastern provinces and growing nationwide usage.
• Comoros, Mozambique, Rwanda, Burundi, Somalia, and parts of Zambia: smaller but notable communities.

If you’d like, I can provide a concise country-by-country summary with approximate number of speakers and official status.