Osun State will hold its governorship election on 15 August 2026 to decide who will govern the state from 2026 to 2030. 

For more than two decades, every governorship election in Osun State has ended in post-election litigation, making it one of Nigeria’s states where election petitions and tribunal rulings have repeatedly led to changes in administration or the overturning of election outcomes. 

Since Nigeria returned to democratic rule in 1999, Osun State has conducted seven governorship elections; every governorship election in Osun, except 1999, has been challenged through an election petition.

The most consequential case came after the 2007 governorship election, which resulted in a change of administration. Following the 2007 governorship election, the Court of Appeal, after nearly three years of litigation, nullified the re-election of Olagunsoye Oyinlola of the People’s Democratic Party (PDP) and declared Rauf Aregbesola of the Action Congress of Nigeria (ACN) the duly elected governor. The ruling produced two lasting consequences. 

First, it changed the administration after almost three years in office, making it one of the few governorship cases in Nigeria where the courts removed an incumbent and installed the opposition candidate.

Second, because Rauf Aregbesola’s tenure was counted from the date he was sworn in rather than from the original election date, Osun’s election cycle shifted permanently. The state subsequently joined seven other states conducting off-cycle governorship elections. 

Although subsequent governorship elections in Osun State have also been challenged, none has resulted in another change of government. Instead, the courts ultimately affirmed the candidates initially declared winners by the Independent National Electoral Commission (INEC). 

These judgments had consequences beyond changing who occupied Government House. Because replacement governors are often sworn in months or even years after the original inauguration dates, they alter the regular election calendar, resulting in the conduct of off-cycle governorship elections.

Prolonged post-election litigation can also affect governance. Extended legal disputes may disrupt policy continuity, delay policy formulation and implementation, and create political uncertainty as governments operate while their mandates remain under judicial review.

Osun’s post-election petitions record 

The 1999 governorship election remains the only one in Osun since Nigeria’s return to democracy that was not followed by a major legal challenge. Since 2003, however, every governorship election in the state has been contested in court.

The 2007 election remains the defining case. Although Olagunsoye Oyinlola of the PDP was initially declared winner, the Court of Appeal, after nearly three years of litigation, nullified his victory in 2010 and declared Rauf Aregbesola of the ACN the duly elected governor, resulting in a change of administration.

Subsequent governorship elections have followed a different pattern. In 2014, Aregbesola, then of the All Progressives Congress (APC), defeated Iyiola Omisore of the PDP. Omisore challenged the result, but both the Election Petition Tribunal and the Court of Appeal upheld Aregbesola’s victory.

The 2018 election also ended in court after Gboyega Oyetola of the APC was declared winner following a supplementary poll. Although the Election Petition Tribunal initially nullified his election, the Court of Appeal reversed the decision, and the Supreme Court affirmed Oyetola’s victory.

Similarly, the 2022 governorship election was challenged after Ademola Adeleke of the PDP defeated incumbent governor Gboyega Oyetola of the APC. The tribunal initially overturned Adeleke’s victory, but the Court of Appeal restored his mandate, a decision later affirmed by the Supreme Court.