Netwealth said in a statement that the new deal will see it provide Stanford Brown clients with managed account portfolios run by its internal investment committee.
"This is a very significant deal for Netwealth and validates the strength and flexibility of what we have developed and can offer the market," Netwealth managing director Matt Heine said.
"We are really pleased to be partnering with such a high calibre group and to be creating new and innovative services for their clients."
Stanford Brown head of private wealth, Vincent O'Neill, said the new deal will see the firm continue to grow.
"Stanford Brown's private wealth division has grown eight-fold in eight years to now manage $1 billion for its clients," Mr O'Neill said.
"We view the adoption of managed accounts as a key factor enabling similar rates of growth to continue well into the future."
Stanford Brown chief executive Jonathan Hoyle said managed accounts offer clients a "superior investment solution".
"There are three clear benefits – a more proactively managed portfolio, lower costs and better tax outcome," Mr Hoyle said.
"When choosing our new technology and platform partner, it was critical that they could provide the necessary functionality but also that their culture was aligned to ours."
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