UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D/A

Under the Securities Exchange Act of 1934

(Amendment No. 18)*

Telecom Italia S.p.A.

(Name of Issuer)

Ordinary Shares with no nominal value

(Title of Class of Securities)

87927W10

(CUSIP Number)

George E. Bushnell III, Esq.

Senior Vice President and Deputy General Counsel

Vivendi S.A

1755 Broadway

New York, New York 10019

Telecopy: (212) 445-3812

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

March 22, 2018

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

2

This Amendment No. 18 (this “Amendment”) amends and supplements the Schedule 13D filed on July 1, 2015 (the “Original Filing”), as amended by Amendment No. 1 filed on October 5, 2015 (“Amendment No. 1”), Amendment No. 2 filed on October 23, 2015 (“Amendment No. 2”), Amendment No. 3 filed on December 17, 2015 (“Amendment No. 3”), Amendment No. 4 filed on January 20, 2016 (“Amendment No. 4”), Amendment No. 5 filed on February 19, 2016 (“Amendment No. 5”), Amendment No. 6 filed on March 1, 2016 (“Amendment No. 6”), Amendment No. 7 filed on March 11, 2016 (“Amendment No. 7”), Amendment No. 8 filed on May 10, 2016 (“Amendment No. 8”), Amendment No. 9 filed on May 20, 2016 (“Amendment No, 9”), Amendment No, 10 filed on November 22, 2016 (“Amendment No. 10), Amendment No. 11 filed on December 6, 2016 (“Amendment No. 11”), Amendment No. 12 filed on December 7, 2016 (“Amendment No. 12”) Amendment No. 13 filed on April 14, 2017 (“Amendment No. 13), Amendment No. 14 filed on May 10, 2017 (“Amendment No. 14”), Amendment No, 15 filed on June 2, 2015 (“Amendment No, 15”), Amendment No. 16 filed on July 31, 2017 (“Amendment No. 16”), and Amendment No. 17 filed on October 2, 2017 (“Amendment 17”, and together with the Original Filing and Amendment Nos. 1 through 16, the “Schedule 13D”) by the Filing Person relating to the ordinary shares, without nominal value (the “Shares”), of Telecom Italia S.p.A., a company formed under the laws of the Republic of Italy (the “Issuer” or the “Company”). Information reported in the Schedule 13D remains in effect except to the extent that it is amended, supplemented, restated or superseded by information contained in this Amendment. Each capitalized term used herein but not defined in this Amendment shall have the meaning assigned to such term in the Schedule 13D.

Item 4. Purpose of the Transaction

Item 4 is hereby amended and supplemented by the addition of the following:

On March 22, 2018, Arnaud de Puyfontaine, Frédéric Crépin and Hervé Philippe, the three members of the Telecom Italia (TIM) Board of Directors representing Vivendi, tendered their resignations from the TIM Board effective as of April 24, 2018, before the Ordinary Shareholders’ Meeting of TIM to be held on that date. Please see Exhibit 1 for more details.

Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that this information set forth in this statement is true, complete and correct.

Dated: March 26, 2018

SCHEDULE I-A

The name and present principal occupation or employment (and the name, principal business and address of any corporation or other organization in which such employment is conducted) of each director of Vivendi are set forth below.

Unless otherwise specified, each person listed below is a citizen of France.

Exhibit 1

Paris, March 22, 2018

Vivendi representatives resign

from Telecom Italia’s Board of Directors

In light of the attempt led by hedge-fund activist Elliott Management, well-known for its track record of short-termist initiatives, to dismantle Telecom Italia (TIM), the three members of the TIM Board of Directors representing Vivendi, which supports the unanimously approved industrial plan led by Amos Genish and his team, have decided to resign from the Board.

As five other Board members have also decided to tender their resignations, resulting in a majority of the Board members having resigned, a Shareholders’ Meeting will be held in May to allow the TIM shareholders to appoint the Board members they want and which policy to follow.

About Vivendi

Vivendi is an integrated content, media and communications group. The company operates businesses throughout the value chain, from talent discovery to the creation, production and distribution of content. Universal Music Group is the world leader in music, engaged in recorded music, music publishing and merchandising. It owns more than 50 labels covering all music genres. Canal+ Group is the leading pay-TV operator in France, also engaged in Africa, Poland, Vietnam and Myanmar. Its subsidiary Studiocanal is the leading European player in production, sales and distribution of movies and TV series. Havas Group is one of the world’s largest global communications group. It is organized in three main business segments covering all the communications disciplines: creativity, media expertise and healthcare/wellness. Gameloft is a worldwide leader in mobile games, with 2 million games downloaded per day. Vivendi Village brings together the Paddington brand’s licensing activities, Vivendi Ticketing (in the United Kingdom, the United States and France), MyBestPro (expert counseling), the venues L’Olympia and Theâtre de L‘Œuvre in Paris, and CanalOlympia in Africa, as well as Olympia Production. With 300 million unique users per month, Dailymotion is one of the biggest video content aggregation and distribution platforms in the world. www.vivendi.com, www.cultureswithvivendi.com