NeoBank

A neobank is a type of direct bank that operates exclusively using online banking without traditional physical branches. In contrast to direct banks, in many cases, neobanks do not have their own banking licenses, and instead rely on partner banks.[1][2][3] They typically have lower operational costs, which can sometimes result in lower fees and more competitive interest rates. https://en.wikipedia.org/wiki/Neobank

Often use 3rd party BaaS (Banking as a Service) partners: the provision of banking products (such as current accounts and credit cards) to non-bank third parties through APIs. This stack can be used with a licensed bank as foundation, a BaaS as middleware, and an ecosystems of FinTechs on top. Chris Skinner suggested a 3-layer representation of the BaaS stack.[2] In this stack, the underlying infrastructure-as-a-service is provided by a traditional, licensed and regulated bank. Above this bank would be the centralized middleware layer that Skinner refers to as "bank as a service". Added on to the bank as a service is a group of decomposed banking services consisting of an ecosystem of fintech startups and service providers. With this technology, based on the BaaS-platform, it is possible to create fintech banks, which could improve banking processes and provide increased convenience for banking clients. In such a constellation, fintech banks are enabled to compete directly with banks by offering core-banking services without having to build all the products that would be needed. https://en.wikipedia.org/wiki/Banking_as_a_service

Largest US neobanks: Chime, SoFi, Varo, Aspiration