Nigerian citizens are required to obtain a visa prior to traveling to Uganda. This means that they couldn't get a visa on arrival and needed to apply for a visa through the appropriate channels before their trip. Uganda Immigration Services provides the e-visa program which allows Nigerian citizens an easy solution to obtain an online visa (e-visa) conveniently. For more details, navigate to the Uganda e-visa requirements for Nigerian citizens section.
However, visa requirements and policies can change over time, so it's important to verify the most up-to-date information before making any travel plans. We recommend checking with the Ugandan embassy or consulate in Nigeria or visiting the Uganda Immigration Services website for the latest information regarding visa requirements, application processes, and any possible changes to the visa policy.