Form 6-K - Report of foreign issuer [Rules 13a-16 and 15d-16]

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 May 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, Turkiye

(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 May 17, 2024, announcing a capital increase of the registrant's subsidiary, Turktell Bilişim Servisleri A.Ş.

Istanbul, May 17, 2024

Announcement Regarding the Capital Increase in Turktell

The capital of our Company’s wholly-owned subsidiary, Turktell Bilişim Servisleri A.Ş. (“Turktell”), has been increased by TRY 5,000,000,000 to TRY 7,974,076,134. In this context, our Company has participated in the capital increase by fully exercising our pre-emptive rights, in accordance with the provisions of the company’s articles of association. One-fourth of the capital was paid in advance before the registration, and the remaining amount will be paid within 24 months.

For more information:

Turkcell Investor Relations

investor.relations@turkcell.com.tr

Tel: + 90 212 313 1888

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.