Former Ministry of Communications Savings Bureau (Iikura, Azabu)

The former Ministry of Communications Savings Bureau (旧逓信省貯金局) was located in Otemachi 2-chome, Chiyoda Ward, Tokyo, on a site with deep roots in Japan's modern communications infrastructure. The area first became associated with government functions when the Bureau of Engraving and Printing was established there in 1876. After the 1923 Great Kanto Earthquake destroyed the Ministry of Communications headquarters in Kobiki-cho, the ministry relocated to temporary structures in Otemachi. The Savings Bureau (貯金局) itself, however, was housed from 1930 in a purpose-built office in Iikura, Azabu (present-day Azabudai, Minato Ward), which served as the ministry's headquarters from 1943 and was demolished in 2019.

During the 1930s and 1940s, the Savings Bureau played a critical role in Japan's wartime financial mobilization. The government aggressively promoted postal savings (郵便貯金) as a patriotic duty, urging citizens to deposit their money into the postal savings system. These funds were then systematically channeled into war bonds and invested in companies supporting wartime production. In April 1938, the National Savings Promotion Bureau (国民貯蓄奨励局) was established to coordinate the nationwide savings campaign. By the war's peak, postal savings represented a major pillar of Japan's war financing, with individual deposits accounting for a significant share of government expenditure.

The Ministry of Communications (逓信省) also exercised control over wartime censorship of mail and telecommunications. As the ministry responsible for Japan's postal and telegraph systems, it played a key role in monitoring and restricting the flow of information during the war years. In November 1943, the ministry was reorganized into the Ministry of Transportation and Communications (運輸通信省), and the Savings Bureau was merged into the Postal Savings and Life Insurance Bureau.

Following Japan's defeat in 1945, more than 6 billion yen in overseas investments tied to the postal savings system evaporated, and depositors were compelled to bear a portion of the state's losses, severely damaging public trust in the system. The Azabu building went on to serve as the headquarters of the Ministry of Posts and Telecommunications until 1969.

In 1964, the Teishin Building in Otemachi became home to the Teishin Comprehensive Museum (逓信総合博物館), nicknamed "Tei-Park" (ていぱーく), which was jointly operated by the Ministry of Posts and Telecommunications, Nippon Telegraph and Telephone Public Corporation (the predecessor of NTT), KDD, and NHK as a comprehensive information and communications museum. The museum closed on August 31, 2013, as part of the Otemachi redevelopment project. The historic Teishin Building was demolished by August 2015, and the Otemachi Place complex, completed in 2018, now stands on the site, incorporating design elements inspired by the original Teishin-style architecture in tribute to the area's communications heritage.