Notice of Partial Redemption of Senior Notes

Kosmos Energy Ltd. announced on September 18, 2026, its intention to partially redeem $25,000,000 of its 7.750% senior notes due 2027. The redemption is scheduled for September 30, 2026. The company reserves the right to conduct further optional redemptions before the final maturity date of the notes. This report does not serve as a formal notice of redemption.