Origins and promulgation
The current Constitution of the Federal Republic of Nigeria was brought into force by the Constitution of the Federal Republic of Nigeria (Promulgation) Decree No. 24 of 1999, signed at Abuja on 5 May 1999 by General Abdulsalami Abubakar, then Head of State and Commander-in-Chief of the Armed Forces, with the text itself taking effect on 29 May 1999 — the day military rule ended and Olusegun Obasanjo was sworn in as President, opening what is now called the Fourth Republic S1. Abdulsalami had become Head of State in June 1998 after the death of General Sani Abacha and oversaw a compressed transition programme that produced the document in under a year S1. He has said in later years that critics who describe the 1999 Constitution as a military-authored text are mistaken, stating publicly that close to 95 per cent of its content was drawn from the 1979 Constitution — itself the work of a Constitution Drafting Committee of 49 civilian legal experts — rather than written by soldiers S1. Other commentators and civil society critics have taken the opposing position that some provisions were altered or inserted during the military-supervised drafting process without the same civilian input, a dispute Abdulsalami has separately acknowledged by calling for the removal of decrees he says were "smuggled" into the final text; neither claim is treated here as settled, and both are attributed to their source S1
Structure of the document
As consolidated with its subsequent alterations, the Constitution runs to roughly 320 sections organised into eight chapters, together with seven schedules S2. Chapter I sets out general provisions, including the supremacy of the Constitution and the definition of Nigeria as a federation; Chapter II lists Fundamental Objectives and Directive Principles of State Policy; Chapter III covers citizenship; Chapter IV guarantees Fundamental Rights; Chapter V establishes the National Assembly and the state Houses of Assembly, covered in detail in national assembly; Chapter VI establishes the federal and state executives, covered in nigerian presidency; Chapter VII establishes the federal and state courts; and Chapter VIII covers the Federal Capital Territory and miscellaneous supplemental provisions S2. The schedules include the First Schedule, which names the states and 774 local government areas discussed in federal structure of nigeria, and the Second Schedule, which divides law-making power between the federal and state levels through the Exclusive and Concurrent Legislative Lists S2
The amendment procedure
Section 9 of the Constitution sets a deliberately demanding bar for change. An ordinary alteration requires the support of not less than two-thirds of all members of each House of the National Assembly, followed by approval through resolution by the Houses of Assembly of not less than two-thirds of the 36 states S3. A narrower category of especially sensitive provisions — among them the creation of new states, adjustment of state boundaries, fundamental human rights, and the procedure for altering the Constitution itself — requires an even higher four-fifths majority in each federal chamber in addition to the two-thirds state ratification threshold S3. This two-stage design, requiring sign-off from both the federal legislature and a supermajority of state legislatures, was intended to prevent unilateral constitutional change by whichever party controls the National Assembly at a given time, and it has in practice caused multiple proposed amendments — including a set of gender-equality bills considered in 2022 — to pass one or both chambers of the National Assembly but fail at state-level ratification S4
Amendment history
Since 1999 the Constitution has been altered five times by name, though the fourth and fifth rounds were each split across several separate Acts covering different subjects. The First and Second Alterations, both in 2010, adjusted electoral timelines and the timing of elections relative to the end of a term of office S2. A Third Alteration, also dated to 2010, made a further discrete change to electoral provisions S2. The Fourth Alteration, comprising five separate Acts assented to in 2017, addressed matters including the financial and administrative autonomy of state legislatures and the judiciary and adjustments to electoral procedure S2. The Fifth Alteration is the largest single round to date: the Ninth National Assembly transmitted around 35 constitutional alteration bills to the President in early 2023, of which 19 received presidential assent by 17 March 2023, comprising seventeen separately numbered Fifth Alteration Acts S5. Their subjects ranged from renaming several local government areas, to granting state Houses of Assembly and state judiciaries financial independence from their state executives, to moving railways from the Exclusive Legislative List to the Concurrent Legislative List, to the Fifth Alteration (No. 17) Act 2023, which permits states to generate, transmit and distribute electricity within areas covered by the national grid — a change reported as a material devolution of federal power over the electricity sector S5S6
Ongoing reform proposals
Constitutional review has continued into the current National Assembly. Reporting in 2025 described a House of Representatives-approved package of more than 80 further alteration bills addressing judicial funding autonomy, electoral reform, proposals for state-level policing, and further fiscal devolution between the federal and state tiers, with a legislative committee targeting completion of the review process by the end of 2025; whether these proposals will secure the two-thirds state ratification Section 9 requires, in whole or in part, had not been finally determined as of mid-2026 S4. Academic and civil society critics cited in this reporting continue to describe the 1999 Constitution as, in their assessment, excessively centralised and a product of its military-era drafting circumstances, a characterisation the site records as an attributed viewpoint rather than an established fact S4