Kyivstar Group Ltd. American Depositary Share Prospectus (Version as of May 26, 2026)

This Supplement is being filed to update, amend and supplement the information previously included in the Prospectus with theinformation contained in our Report on Form 6-K which was submitted to the U.S. Securities and Exchange Commission (the “SEC”)on May26, 2026 and is included immediately following the cover page of this Supplement. This Supplement is not complete without, This Supplement should be read in conjunction with the Prospectus and if there is any inconsistency between the information in theProspectus and this Supplement, you should rely on the information in this Supplement. We may further amend or supplement the Our Common Shares are listed on the Nasdaq Global Select Market under the symbol “KYIV.” On May22, 2026, the last reportedsale price of our common shares was $14.20 per share. Investing in our securities involves a high degree of risk. See “Risk Factors” beginning on page 11 of the Prospectus for adiscussion of information that should be considered in connection with an investment in our securities. Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of thesesecurities or determined if the Prospectus or this Supplement is truthful or complete. Any representation to the contrary is acriminal offense. The date of this Supplement is May 26, 2026. UNITED STATESSECURITIES AND EXCHANGE COMMISSION FORM 6-K REPORT OF FOREIGN PRIVATE ISSUERPURSUANT TO RULE 13a-16 OR 15d-16 UNDER For the Month of May 2026 Kyivstar Group Ltd.(Translation of registrant’s name into English) Unit 517, Level 5Index TowerDubai International Financial Centre (DIFC) Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.Form 20-FForm 40-F EXPLANATORY NOTE This Amendment No. 1 to the Form 6‑K filed on May 26, 2026 (“Form 6‑K/A”) is being furnished to disclose the previously omittedaggregate purchase price for the acquisition of six solar power plants in the Lviv region, which totaled USD 80.8mn (UAH 3.6bn).Except for the inclusion of the aggregate purchase price, the information set forth in the original Form 6‑K remains unchanged. Copies Description of ExhibitPress release dated May 26, 2026Investor Presentation, dated May 26, 2026 Exhibit No. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed onits behalf by the undersigned, thereunto duly authorized. Kyivstar Group Ltd. Date: May 26, 2026 By: /s/ Boris DolgushinBoris DolgushinChief Financial Officer