6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of September 2024

Commission File Number: 001-15092

TURKCELL ILETISIM HIZMETLERI A.S.

(Translation of registrant’s name into English)

Aydınevler Mahallesi İnönü Caddesi No:20

Küçükyalı Ofispark

34854 Maltepe

Istanbul, Turkey

(Address of Principal Executive Offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F:

x Form 20-F  ¨ Form 40-F

Enclosure: A press release dated September 19, 2024, announcing the registrant's decision to issue Lease Certificates.

Istanbul, September 19, 2024

AnnouncementRegarding the Decision to Issue Lease Certificates

Our Company's Board of Directors resolved that our wholly owned subsidiary Turkcell Ödeme ve Elektronik Para Hizmetleri A.Ş. shall issue management agreement based lease certificates (sukuk) in accordance with capital markets legislation through an asset leasing company based in Turkey at an amount of up to TRY 1.5 billion, in Turkish Lira terms, with maturities up to 12 months, in the domestic market, in one or more tranches, without a public offering, as a private placement and/or to be sold to institutional investors. The respective issuance is subject to the approval of the Capital Markets Board.

Formore information:

TurkcellInvestor Relations

investor.relations@turkcell.com.tr

Tel: + 90 212 313 1888

Disclaimer

This pressrelease does not constitute an offer to sell, or a solicitation of offers to purchase or subscribe for securities in the United Statesor any other jurisdiction in which such offer or solicitation would be unlawful. The securities referred to herein have not been andwill not be registered under the U.S. Securities Act of 1933, as amended (the "Securities Act"), and may not be offered, sold or deliveredwithin the United States or to or for the benefit of, US persons (as defined in Regulation S under the Securities Act) absent registrationor an applicable exemption from the registration requirements of the Securities Act. This press release is being issued pursuant to andin accordance with Rule 135c under the Securities Act.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, Turkcell Iletisim Hizmetleri A.S. has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.