• NTT Docomo has been building up a portfolio of financial services assets over the past two years
• Now it is set to acquire a majority stake in online banking firm SBI Sumishin Net Bank 
• Its local rivals already have diversified financial services operations

Keen not to be left behind in Japan’s digital financial services sector, NTT Docomo is set to acquire a near 66% stake in SBI Sumishin Net Bank for about 233.7bn yen ($1.61bn) through a deal with financial services conglomerate SBI Holdings and Sumitomo Mitsui Trust Bank. 

NTT Docomo has struck a deal to acquire the 34.19% stake in SBI Sumishin Net Bank currently held by SBI Holdings and has launched a tender offer to acquire shares from other minority stake holders that would eventually give it a 65.81% stake in the established ‘neobank’. 

Sumitomo Mitsui Trust Bank will hang on to its 34.19% stake in SBI Sumishin Net Bank, meaning it will have 50% of the voting rights in SBI Sumishin Net Bank while NTT Docomo will hold the other 50%. SBI Sumishin Net Bank will become a consolidated subsidiary of NTT Docomo. 

As a result of the agreement, SBI Holdings and Sumitomo Mitsui Trust Bank will collaborate with NTT Docomo to further develop the neobank’s digital financial services offerings. 

“By welcoming SBI Sumishin Net Bank into the Docomo Group, Docomo will make a full-scale entry into the banking industry and aim to further increase the corporate value of SBI Sumishin Net Bank by combining Docomo’s diverse channels, such as its membership base and Docomo Shops, with Sumitomo Mitsui Trust Bank’s banking management and advanced trust service know-how,” noted Docomo in this announcement (in Japanese). 

In addition, NTT Docomo and SBI Holdings say they will combine their respective strengths “to quickly and appropriately respond to diversifying customer needs in a rapidly evolving digital society and providing innovative services in various fields, with the financial sector at the core.” The companies will collaborate to develop “next-generation financial services” and develop new propositions “in the fields of asset management, security tokens, and insurance”. NTT Docomo will also acquire an 8.2% stake in SBI Holdings for 110.8bn yen ($764m). 

The acquisition of SBI Sumishin Net Bank will help NTT Docomo to rival the broader financial services offerings of its domestic rivals, KDDI, Rakuten Mobile and SoftBank, all of which already include banking services in their fintech portfolios. 

As part of its ‘smart life’ strategy, NTT Docomo has been building up its fintech portfolio over the past couple of years: In late 2023 it set up a joint venture with Monex to provide a digital platform for investors to manage their financial assets and portfolios and in 2024 it acquired Orix Credit in order to offer loans to its customers. It also has a loyalty rewards programme called ‘d points’, but this latest move will help it expand into the broader banking services sector.

That, in turn, will boost its chances of strengthening customer loyalty in a market that is increasingly competitive, especially in terms of positioning mobile connectivity as the foundation for a broad range of digital services and reward schemes, which has been the key to Rakuten Mobile’s entry into the Japanese market. (Though in the case of Rakuten, it started with the digital services portfolio and added its own mobile network and operations to the mix). 

Docomo noted: “By providing Docomo’s financial services, such as bank accounts, payments, and securities in an integrated manner, [customers] will be able to conveniently use everything from savings, payments, investments, insurance, loans and points all in one place with just one smartphone. We will also provide advantageous systems, such as giving d point rewards for using multiple services.”

It added: “By combining data obtained through banking services with data from other financial services, we will deepen our understanding of our customers and propose the best services at the best time… By incorporating banking functions that are essential to our customers’ lives, we aim to increase the number of customers for Docomo’s financial services overall. We will also deepen our relationships with customers by encouraging them to combine our new banking services with existing Docomo services.”

At the beginning of 2025, SBI Sumishin Net Bank reported 8 million banking account customers, while NTT Docomo, Japan’s largest mobile operator, boasted more than 91 million customers at the end of March this year. It’s not known how much overlap there is between the two customer bases. 

The mobile operator’s parent, NTT Group, recently refreshed Docomo’s management team as part of a broader company reset – see NTT to take full control of NTT Data and rejigs Docomo.

- Ray Le Maistre, Editorial Director, TelecomTV