Turkcell (NYSE: TKC) raises Turktell capital to TRY 37.22B in cash

Rhea-AI Filing Summary

Turkcell İletişim Hizmetleri A.Ş. reported that it has injected new capital into its wholly-owned subsidiary Turktell Bilişim Servisleri A.Ş.. Turktell’s share capital was increased by TRY 15,000,000,000 to a new total of TRY 37,220,306,252. Turkcell exercised its pre-emption rights in full and paid the entire increase in cash, meaning the additional funds were provided directly by the parent company. This transaction strengthens the financial base of Turktell while preserving Turkcell’s full ownership.

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 December 2025

Commission File Number: 001-15092

TURKCELL İLETİŞİM HİZMETLERİ A.Ş.

(Translation of registrant’s name into English)

Turkcell Küçükyalı Plaza

Aydınevler Mahallesi İnönü Caddesi No:20

Küçükyalı Ofispark

34854 Maltepe
Istanbul, Türkiye

(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 December 8, 2025 announcing the capital increase of the registrant's wholly-owned subsidiary, Turktell Bilişim Servisleri A.Ş.

Istanbul, December 8, 2025

Announcement Regarding Turktell Bilişim Servisleri A.Ş. Capital Increase

The capital of our Company's wholly-owned subsidiary, Turktell Bilişim Servisleri A.Ş. (“Turktell”), has been increased by TRY 15,000,000,000 to TRY 37,220,306,252. Our Company's pre-emption rights with respect to the capital increase is fully paid in cash.

For more information:

Turkcell Investor Relations

investor.relations@turkcell.com.tr

Tel: + 90 212 313 1888

1

SIGNATURES

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

	TURKCELL İLETİŞİM HİZMETLERİ A.Ş.
Date: December 8, 2025	By:	/s/ Özlem Yardım
		Name:	Özlem Yardım
		Title:	Investor Relations Corporate Finance Director

	TURKCELL İLETİŞİM HİZMETLERİ A.Ş.
Date: December 8, 2025	By:	/s/ Kamil Kalyon
		Name:	Kamil Kalyon
		Title:	Chief Financial Officer

FAQ

What did Turkcell (TKC) announce in the December 2025 6-K?

Turkcell announced a capital increase at its wholly-owned subsidiary Turktell Bilişim Servisleri A.Ş., which was fully funded by Turkcell in cash through its pre-emption rights.

How much capital was injected into Turktell Bilişim Servisleri A.Ş. by Turkcell?

Turktell’s capital was increased by TRY 15,000,000,000, bringing its total share capital to TRY 37,220,306,252.

Did Turkcell’s ownership in Turktell change after the capital increase?

No. The filing states that Turktell is a wholly-owned subsidiary of Turkcell and that Turkcell fully exercised its pre-emption rights in the capital increase, preserving full ownership.

Was the Turktell capital increase paid in cash or in kind?

The filing states that Turkcell’s pre-emption rights relating to the capital increase were fully paid in cash.

Why is the Turktell capital increase relevant for Turkcell (TKC) investors?

The transaction shows Turkcell providing TRY 15,000,000,000 of new cash capital to Turktell, which reinforces the subsidiary’s financial position while remaining fully under Turkcell’s control.