KDD, one of the company's predecessors, was established in 1953. In 1952, responsibility for the telecommunications business, previously handled by the Ministry of Communications after the war, was transferred to Nippon Telegraph and Telephone Public Corporation. The following year, KDD was established to handle international telegraph and telephone services.
Established International Telegraph and Telephone Company, Limited (KDD).
Successfully received the first television transmission between Japan and the United States at the Ibaraki Space Communications Laboratory.
The First Trans-Pacific Cable (TPC-1) went into service. It connected Kanagawa Prefecture and Guam, and extended via Hawaii to the U.S. mainland. This made it possible for approximately 100 people in Japan and the United States to make calls simultaneously (with 128 circuits in the original design). The total length of the cables constructed to date is approximately 1,200,000 km, equivalent to about 30 times the circumference of the Earth.
KDD opened the first Trans-Pacific Cable (TPC-1). The first submarine cable, TPC-1 (Trans Pacific Cable-1), connecting the Ninomiya Submarine Cable Relay Station in Kanagawa Prefecture with Guam and continuing via Hawaii to the U.S. mainland, opened on June 19, 1964. Using coaxial submarine cable, it had a small capacity equivalent to 128 telephone circuits and carried communications between Japan and the United States for the following 26 years, until 1990.
KDD joined the International Telecommunications Satellite Organization (Intelsat).
KDD opened the Ibaraki Satellite Communications Station and began television transmission between Japan and the United States.
KDD opened the Yamaguchi Satellite Communications Station and established a satellite link with Europe.
KDD launched international direct-dial service.
KDD Building completed (Shinjuku, Tokyo).
KDD joined the International Maritime Satellite Organization (Inmarsat).
June 1, 1984
創業
Daini Denden Planning established.
Nippon Telecom Co., Ltd. (TWJ) established.
Exhibited at the International Science and Technology Exposition, Tsukuba '85. KDD (as it was then known) operated its own pavilion at the International Science and Technology Exposition—Tsukuba '85 for six months, from March 17 to September 16, 1985.
The Telecommunications Business Act took effect (liberalization of telecommunications).
Daini Denden Inc. (DDI) launched.
Tokyo Telecommunications Network Co., Inc. (TTNet) established in the Kanto region as a regional telecommunications company.
DDI launches dedicated services on the Tokaido route (Tokyo, Nagoya, and Osaka).
Nippon Idō Tsūshin Corporation (IDO) is established.
Kansai Cellular Telephone Co., Ltd. is established.
DDI launches long-distance telephone services on the Tokaido route (Tokyo, Nagoya, and Osaka).
Kyushu Cellular Telephone Co., Ltd. is established.
Chugoku Cellular Telephone Co., Ltd. is established.
Tohoku Cellular Telephone Co., Ltd. is established.
Hokuriku Cellular Telephone Co., Ltd. is established.
Hokkaido Cellular Telephone Co., Ltd. is established.
IDO launches automotive and mobile phone services using the high-capacity system. This was the first new entrant in the automotive telephone business, which had been monopolized by NTT.
KDDI America was established in 1989 as a telecommunications business to support Japanese multinationals
KDD opens the Pacific's first optical submarine cable, the Third Pacific Transoceanic Cable (TPC-3). Stretching 13,300 km from the Chikura Submarine Cable Relay Station via Guam to Hawaii and the U.S. mainland, it was the world's longest cable at the time.
Shikoku Cellular Telephone Co., Ltd. is established.
The first optical submarine cable across the Pacific, the Third Trans-Pacific Cable (TPC-3), went into service. Thanks to technological innovation, capacity increased dramatically from TPC-1's 128 circuits to 7,560.
IDO launches its Handy Phone mobile phone service.
IDO launched its “Handy Phone” mobile service. Alongside the shoulder-carried phones that symbolized the bubble era, compact handheld mobile phones also appeared. Phones had entered an era of being held in one hand, especially in business settings.
KDD America is launched in New York, serving US based customers
Kansai Cellular launches services using the TACS system.
KDDI America establishes Chicago office
Okinawa Cellular Telephone Co., Ltd. is established.
Tu-Ka Cellular Tokyo, Inc. is established.
Tu-Ka Phone Kansai, Inc. is established.
IDO launches services using the TACS system.
Tu-Ka Cellular Tokai, Inc. is established.
DDI completes its nationwide service network.
IDO and the Cellular Group begin nationwide TACS roaming and interconnection
DDI lists on the Second Section of the Tokyo Stock Exchange
The mobile phone handset sales system begins
The “mobile phone sales system” was introduced, allowing users to buy the phones that telephone companies had previously rented out. As a result, users no longer had to pay a large security deposit, helping mobile phones spread among young people.
IDO launched digital service.
DDI lists on the First Section of the Tokyo Stock Exchange (section transfer)
DION service launches
KDD and TWJ merge, and the company changes its name to KDD Corporation
IDO and the Cellular Group complete a nationwide seamless cdmaOne network
IDO and the Cellular Group launch EZweb, an Internet access service for mobile phones
The nationwide seamless cdmaOne network was completed, and “EZweb,” an internet access service for mobile phones, was launched. This marked the beginning of a historic service that came to symbolize feature phones.
The nine companies in the DDI Pocket Telephone Group merge
IDO and the Cellular Group launch au, a unified nationwide mobile brand
The au service was launched.
DDI CORPORATION, KDD Corporation and IDO CORPORATION merge to form a new company. KDDI CORPORATION
DDI, KDD, and IDO merged, establishing DDI Corporation (KDDI).
DDI, KDD, and IDO merge, forming DDI Corporation (KDDI)
Seven companies in the Cellular Group merge, forming au Corporation
The company changes its name to KDDI Corporation
The telephone carrier selection service My Line launches
KDDI America merges with TELECOMET International Inc., to strengthen solutions services
au Corporation is merged into the company
Regional telecommunications companies TTNet, Osaka Media Port (OMP), and Chubu Telecommunications (CTC) spin off their corporate data communications services, forming Powerdcom Inc.
A GPS mobile phone equipped with the first electronic compass in a mobile phone goes on sale
GPS mobile phones equipped with the first-ever electronic compass in a mobile phone went on sale. For the first time, GPS-based map services—now indispensable—were made available on mobile phones.
The first model in the au design project, “INFOBAR,” went on sale. It was the first in a renowned design series that remains beloved today.
Third-generation mobile phone service (CDMA2000 1x) launches
The music download service Chaku-Uta® launches
KDDI strategically invests in TELEHOUSE America
TTNet and Powerdcom merge, and the company adopts the name Powerdcom
Launched the fiber-optic service “KDDI Hikari Plus” (now au Hikari).
Launched “EZ Navi Walk,” a navigation service for pedestrians.
Launched “CDMA 1X WIN,” a third-generation mobile phone service using CDMA2000 1x EV-DO technology.
Released “INFOBAR,” the first model in the au design project.
Transferred the DDI Pocket telephone business to Carlyle and Kyocera.
Launched “Chaku-Uta Full®.”
Launched the IP telephone service “Metal Plus Phone.”
Exhibition at the 2005 World Exposition, Aichi, Japan (Expo 2005 Aichi). For six months, from March to September 2005, we supported the smooth operation of the Expo through initiatives that made use of the latest IT technologies, including a comprehensive information center, a visitor reservation system, a support navigation system, and the hybrid information device “Ai-MATE.”
Merged Tu-Ka Cellular Tokyo, Inc., Tu-Ka Cellular Tokai, Inc., and Tu-Ka Phone Kansai, Inc.
Entered into a comprehensive partnership with the Tokyo Electric Power Group in the telecommunications business.
Began sales of the world’s first mobile phone compatible with “One-Seg” mobile TV broadcasting.
Merged with Poweredcom.
Launched “LISMO,” an integrated music service.
Integrated the FTTH business with Tokyo Electric Power.
Made the JCN Group a consolidated subsidiary.
Established Wireless Broadband Planning Corporation (now UQ Communications Inc.).
Launched the “au Smart Sports Run&Walk” service. “au Smart Sports” was a new service seamlessly connecting au mobile phones and PCs to offer customers a new way to enjoy sports.
When it launched in 2008, visiting branches and ATMs was the norm. We recognized the potential of mobile phones early on and aimed to create an environment where people could use banking services anytime, anywhere. Today, the service has become an established part of people’s lives, with more than 7.14 million accounts and deposits exceeding 5.5 trillion yen.
Ended Tu-Ka services.
Transformed Wireless Broadband Planning Corporation into an operating company and launched UQ Communications Inc.
Acquired shares in CTC and made it a consolidated subsidiary.
Launched services for “Jibun Bank” (now au Jibun Bank), a mobile online bank jointly established with The Bank of Tokyo-Mitsubishi UFJ.
Launched “au Matome Talk,” offering free domestic calls between au mobile phones and KDDI landlines
Started offering the “Giga-Toku Plan,” with speeds of up to 1 Gbps, on Hikari one Home
The “Jibun Bank” (now au Jibun Bank) service was launched.
UQ Communications launched “UQ WiMAX,” a broadband communications service using mobile WiMAX technology
Announced “iida,” a new brand for au mobile phones
UQ Communications launched commercial “UQ WiMAX” services
Acquired an equity stake in Jupiter Telecommunications Co., Ltd. (J:COM) (now JCOM Co., Ltd.)
Established a planning company for e-book distribution (now Booklista) with Sony, Toppan Printing, and The Asahi Shimbun Company
Established KDDI Matomete Office Corporation
Launched “au Sonpo,” a mobile non-life insurance service jointly established with Aioi Nissay Dowa Insurance
Released the “iPhone 4S” (made by Apple)
Refreshed the au brand logo
The au brand mark was refreshed alongside the brand slogan “A New Freedom.”
Launched “au Smart Value” and “au Smart Pass”
Released the “iPhone 5” (made by Apple)
Launched “au 4G LTE,” a next-generation high-speed communications service
Expanded “KDDI Matomete Office” nationwide
Released the “iPhone 5s/5c” (made by Apple)
Launched “au Smart Value mine”
The actual population coverage rate of the 800 MHz platinum-band “4G LTE” service reached 99%
Integrated the management of J:COM and JCN
Launched the “au WALLET” service
Launch of smartphones equipped with both LTE-Advanced (CA) and WiMAX 2+
Launched a joint business in collaboration with Myanmar Posts and Telecommunications (MPT), the state-owned postal and telecommunications operator
Launched au's new pricing plan, “Kakeho and Digira”
Established KDDI Value Enabler Corporation
Launched the “iPhone 6” and “iPhone 6 Plus” (manufactured by Apple)
Started issuing the “au WALLET Credit Card”
Launched “au VoLTE,” a next-generation voice calling service
Launched the “au WALLET Market” service
Launched “au Denki,” au's electricity service
Launched “au Insurance and Loans,” a financial service
The “Reviving Memories on Your Mobile Phone” initiative was launched. We began restarting phones that would no longer power on, retrieving precious memories, and giving customers printed photos.
Launched the “au STAR” membership program
Acquired shares in BIGLOBE, making it a consolidated subsidiary
Launched au's new pricing plans, “au Pitatto Plan” and “au Flat Plan”
Launched “au HOME,” a home IoT service
Made Soracom, Inc. a consolidated subsidiary
Made AEON Holdings Co., Ltd. a consolidated subsidiary
Launched “KDDI IoT Connect LPWA” IoT connectivity service
Opened “KDDI DIGITAL GATE,” a digital business development hub, in Toranomon, Tokyo
Established au Financial Holdings, Inc., an intermediate financial holding company, and launched the Smart Money initiative
Launched “au PAY,” a smartphone payment service
New brand slogan: “Tomorrow, Together.” The brand slogan “Designing The Future,” used since the company was established in 2000, was replaced with “Tomorrow, Together.” The au brand slogan was also refreshed: “For a more exciting future.”
The possibilities opened up by 5G, whose services began in 2020, will have a major impact on areas such as smart cities and autonomous driving. Its communication speeds are sure to exceed your expectations.
Launch of au 5G, the fifth-generation mobile communications service
Changed au points to the shared loyalty points program, Ponta Points
Integrated the UQ mobile business of UQ Communications, Inc.
Launched povo, a new online-only pricing brand, strengthening the multi-brand strategy
The online-only new pricing brand “povo” was launched, strengthening the multi-brand strategy. The era had arrived when smartphone contracts could be completed entirely online. The nature of mobile brands also changed significantly, with options such as flexible add-ons tailored to each person's lifestyle.
Introduced service monitoring using operations automation functions at both the Tokyo and Osaka sites
Established KDDI Smart Drone, Inc., a drone business company
Ended the CDMA 1X WIN service for 3G mobile phones
Established au Energy Holdings, Inc., an intermediate holding company
Established KDDI Digital Divergence Holdings, an intermediate holding company, and strengthened support for and development of customer DX initiatives
Formulated KDDI VISION 2030
Began operating au base stations using Starlink satellite broadband internet
Launched αU, a metaverse and Web3 service
Launched the au Money Activity Plan, the first in the mobile industry to bundle communications services with financial benefits
Mitsubishi Corporation, KDDI, and Lawson signed a capital and business alliance agreement
Launched KDDI BUSINESS as the corporate business brand in Japan and overseas
First-time exhibitor at MWC Barcelona 2024, the world's largest mobile industry trade show. MWC GSMA Life Transformation Enhancing the power to connect.
ELYZA and the KDDI Group signed a capital and business alliance agreement to promote the practical application of generative AI in society
Launched WAKONX, a business platform for corporate customers
Launched MUGENLABO UNIVERSE, a space co-creation program
Launched “WAKONX,” a business platform for the AI era, for corporate customers. WAKONX
Expanded “Mountain Hut Wi-Fi,” powered by Starlink, to 100 locations, including Japan's 100 Famous Mountains.
Ranked first in 13 categories in Opensignal's analysis of the mobile network experience.
Ponta Pass, which offers great deals on shopping at Lawson and more, launches on October 2. Ponta Pass image
At Expo 2025 Osaka, Kansai, as part of the Future Society Showcase Project, “Future Life Expo: Future City,” KDD participated as a Platinum Partner and held a joint exhibition with Hitachi, Ltd. on the theme of “Society 5.0 and the Future City.”
World first: Satellite data communications via au Starlink Direct launch. au STARLINK
New brand slogan: “Spark Your Journey” KDDI wants to support its customers as they take on new challenges, and has created the new brand slogan “Spark Your Journey.”
Starting at 6:00 a.m. on October 28, 2026, the carrier email services of au and UQ mobile are unavailable or difficult to use nationwide. Sending emails is possible, but receiving emails and the "au Mobile Email Carrying Service" are also affected. Voice calls and data communication remain unaffected.
From 6:00 a.m. on October 28, 2026, the email services (carrier mail) of au and UQ mobile are unavailable or difficult to use nationwide. Email sending remains possible, and voice calls and data communication are unaffected. KDDI deeply apologizes for the inconvenience to customers and is working to improve the situation.
From 6:00 a.m. to 1:40 p.m. on October 28, 2026, an outage occurred in the email services of au and UQ mobile. The service was affected nationwide, and the email service has been restored. After restoration, queued emails will be delivered sequentially. We apologize for the inconvenience caused to our customers.
Since 6:00 a.m. on October 28, 2026, au email service has been unavailable nationwide. Voice calls and data communications remain available as usual.
Since 6:00 a.m. on October 28, 2026, au email service has been unavailable or difficult to access across Japan. Voice calls and data services remain available as usual. The cause is under investigation, and information on the expected restoration time will be provided once it is known.
From 6:00 a.m. on October 28, 2026, nationwide, the carrier email services of au and UQ Mobile, as well as the "au Mail Portable Service", are unavailable or difficult to use. Voice calls and data communication remain available as usual. No specific recovery outlook has been provided.
From 6:00 a.m. on October 28, 2026, nationwide, the carrier email services of au and UQ mobile, as well as the 'au Mail Mobile Service', are unavailable or difficult to use. Voice calls and data communication remain available as usual. An estimate of restoration will be provided as soon as it becomes known.
From 6 a.m. on October 28, nationwide au and UQ mobile email services have been unavailable or difficult to use. The email infrastructure is under high processing load, and no unauthorized intrusion into our system has been confirmed to date. If initial settings are already configured, au email can be accessed via webmail from a browser.
Starting at 6:00 a.m. on October 28, 2026, email services for au and UQ mobile are unavailable or difficult to use nationwide. Sending emails has become possible, but difficulties persist, including with the 'au mobile email carry service'.
As of 9:00 a.m. on October 26, 2026, due to the impact of Typhoon No. 30, communication services are unavailable or difficult to use in parts of Ishigaki City, Okinawa Prefecture. The impact has been ongoing since 10:11 a.m. on October 23. Taketomi Town in the Yaeyama District of Okinawa Prefecture has been restored, and the affected services include au, UQ mobile, povo, and MVNOs using au lines.