S&P Global Upgrades ONEOK’s Credit Rating After $9B Apollo Investment Boosts Debt Profile

ONEOK Inc. (NYSE: OKE) has seen its issuer credit rating raised to ‘BBB+’ from ‘BBB’ by S&P Global Ratings, with the outlook stabilized following a transformative $9 billion minority equity investment from Apollo, announced Sept. 10, 2026. The upgrade reflects improved financial leverage and successful debt reduction, according to the rating agency.

S&P Global noted that ONEOK applied approximately $5 billion of the Apollo proceeds to pay down existing debt and complete a cash tender offer, significantly reducing leverage at the operating company level. The agency now forecasts adjusted debt-to-EBITDA to remain in the low-3x range through 2027, underpinning its stable rating outlook.

The upgrade removes ONEOK from CreditWatch Positive, affirming confidence in the company’s ability to integrate the planned acquisition of Brazos Midstream’s Permian Midland Basin assets later this year and maintain financial discipline. The short-term ‘A-2’ rating was confirmed alongside the upgrade.

Strategic Integration and Balance Sheet Strength

The infusion of capital and ensuing debt reduction fortify ONEOK’s balance sheet while enabling the strategic acquisition of Brazos Midstream’s Permian Midland Basin gathering and processing assets. S&P Global expects seamless integration of these assets to support the company’s well-established midstream franchise.

The minority equity investment is structured with a capped internal rate of return of 7% for Apollo over the first nine years and limits HoldCo to discretionary distributions from OpCo. No debt will reside in the HoldCo, and Apollo holds limited consent rights without board representation, reinforcing financial governance and control integrity.

Implications for Investors

The rating upgrade marks a pivotal moment for ONEOK, improving its debt profile and reinforcing its credit standing. Investors may view the stronger balance sheet and consolidation strategy as enhancing long-term stability and strategic flexibility, particularly ahead of the Brazos integration.

That said, risks remain tied to integration execution and maintaining leverage within the projected range. Any deviation toward more aggressive financial policies could prompt rating reassessment, as S&P has indicated.

With ONEOK trading at $88.63 as of Sept. 25, 2026—a 2.28% decline that day—the credit upgrade offers a counterbalance to recent volatility, providing a strong signal of financial health amid broader market uncertainties.