The new tax Acts are live: what changed on 1 January 2026

Nigeria's tax reform legislation, enacted in June 2025, is now in force. The Nigeria Tax Act and the Nigeria Tax Administration Act apply to transactions occurring from 1 January 2026. The Nigeria Revenue Service Establishment Act and the Joint Revenue Board Establishment Act had already taken effect in June 2025 and were activated alongside them.

Two dates matter for planning. On 1 January 2026 the substantive provisions began to apply, and on 3 February 2026 the Nigeria Revenue Service issued a memo clarifying how the new laws apply to filings made in the transition — including returns filed in January 2026 that relate to earlier periods. Companies that filed early in the year on the assumption that the new rules applied retrospectively should check that position.

The National Assembly also released certified versions of the four Acts in January 2026, intended to resolve reported discrepancies between the harmonised bills and the gazetted texts. Advisers have since noted that gaps and inconsistencies remain in the certified versions, so where a provision is genuinely unclear it is worth taking a documented position rather than assuming settled practice.

For most of our corporate clients the immediate work is unglamorous: confirm which regime governs each open filing period, align the accounting records with the returns being filed, and keep a written note of the basis for any judgement call. That note is what protects the directors if the treatment is later queried.

We are advising clients on commencement and transition questions on a matter-by-matter basis. If a transaction straddles the change of regime, tell us before you file, not after.