The Japanese savings rate rose to around 10 percent in the early 20th century. The growth of individual savings supported and stabilized this high savings rate. This paper examines how and why the individual savings grew in modern Japan. The Japanese Postal Savings Bank was the first nation-wide saving bank for ordinary people's small savings, and became generally popular at the beginning of 20th century as the savings rate rose. This paper therefore focuses on the spread of the Postal Saving Bank's individual deposit accounts. Previous studies have revealed that central government policy promoting individual savings affected deposits in the Postal Savings Bank. But government policy was not the only factor which induced people to save. Various local organizations and their actions also widely affected ordinary people's saving behaviors. The experience of Mishima City in Shizuoka Prefecture provides a good example of how saving behavior spread in local society. In Mishima, new modern organizations such as the local post office, elementary schools and local government, were well aware of the central government policy promoting savings, and additionally they had influence in the local community. To give one example, Mishima elementary school cooperated with Mishima post office to promote making small savings to parents through school children. As the government implemented systems to promote postal savings, local community leaders tried to utilize those systems. Additionally, these local leaders did not just accept this policy; to a certain extent they could also give advice to government about it. It was not only the modern but also the older parts of society that joined in the promotion of savings. In Mishima, local small savings organizations such as mujin (pre-modern mutual financing communities) and local residents' unions were promoted by local government and local post offices. Although there were a variety of purposes for savings, these savings movements lead the growth of small deposits in local modern banks, similar to postal savings. As the postal savings system developed in local communities, pre-modern collective savings were integrated to the modern system and the new generation was trained in the concept of saving. This happened all over Japan, not only in Mishima. In the early 20th century, Japanese local society was in many respects being reconstructed. Savings behavior and the promotion of individual saving was one typical trend in this process. This movement affected the Japanese national savings rate, and to a certain extent supported capital accumulation for Japanese modernization.