Littner was a director at American Express, while before that he led a priority bank project with Lloyds Bank.
Boost Capital hailed Littner as a seasoned commercial finance leader with extensive experience in business development, marketing and product management who will drive the business to the next level.
Marc Glazer, chief executive of Boost Capital, said: “Alexander brings a wealth of knowledge to Boost Capital from his experience in business development and leadership roles across many different regions and disciplines.
“He holds an in-depth appreciation of the needs of small business owners and has previously been a driving force in implementing change and growing businesses – it is because of these skills that he is a fantastic fit for Boost Capital.
“I thoroughly look forward to him driving the development of the UK business, and in turn helping UK SMEs to grow.”
Littner added: “I am thrilled to be joining an innovative and dynamic company who is taking on the challenge of changing perceptions on SME finance in the UK.
“As the economy is now recovering, growing their business and finding the capital to do so is something that is at the forefront of small business owners’ minds.
“Matching the demand for funding with the Boost Capital offering is something that I am excited about being involved in.”
