Our story
How we got here
In 1996, while still a university student, Cathy Guo rented two desks inside a travel agency in Ashfield with a classmate. Their first service was simple: helping Chinese international students and working-holiday visitors claim tax refunds – completing forms by hand and entering them one by one.
It was painstaking work. But Cathy had identified something real: many new arrivals from Mainland China were not only unfamiliar with the Australian tax system. They were looking for someone who could help them navigate a new country in their own language, with patience and genuine care.
That first venture lasted just one year. But those two desks were the true beginning of Addsum – carrying not just the courage of a first attempt, but the values that would define everything that followed.
1996
The beginning
While finishing her accounting degree, Cathy Guo rents two desks in a travel agency in Ashfield, helping Chinese students and working-holiday visitors claim tax refunds.
2002
Building a reputation in Eastwood
Cathy opens Addsum’s first accounting office in Eastwood. When her business partner returns to Hong Kong for family reasons, she continues alone: printing and distributing flyers door to door and building a client base one relationship at a time.
2003
Lending services established
Cathy identifies a deeper need among her growing client base, which includes new migrants and small business owners: access to finance. She explains their stories in language lenders understand and invites David Xu, a finance and property expert, to co-found Addsum’s lending practice.
2006
Sydney CBD office opens
Addsum acquires a CBD presence, the same year it welcomes its first Chinese enterprise client – who remains with Addsum today.
2008
First partner joins
The firm’s first partner appointment brings Big Four discipline and structure to a growing practice, beginning a partnership model that will define the firm’s next two decades.
2011-2013
Derek Wang and Sunday Jiang join as partners
Derek Wang joins in 2011, bringing cross-border audit, tax and advisory experience across Mainland China, Australia and Hong Kong. In 2013, Sunday Jiang joins as finance and lending partner, enabling more complex, large-scale transactions.
2012
Martin Place headquarters established
As Addsum’s Chinese enterprise practice grows, it acquires a dedicated office in Martin Place, keeping the firm closely connected to the clients it has spent years building relationships with.
2016
Addsum Foundation launched
Addsum formalises its long-standing commitment to community through the Foundation, which supports education, social welfare, health, technology and cultural initiatives across Australia and the Asia-Pacific.
2017
Sheldon Mak joins as tax partner
Hong Kong-born accountant/lawyer Sheldon Mak joins to strengthen the firm’s capability in complex international tax and intergenerational wealth structuring.
2019
109 Pitt Street
Addsum purchases the full floor at Level 19, 109 Pitt Street and uses the COVID disruption of 2020 as an opportunity to transform the space into a modern, professional environment that reflects the firm’s growth and its commitment to its people.
2020
Asset management launched
Addsum establishes its asset management capability, enhancing the firm’s ability to support clients in structuring, managing and optimising their property and investment holdings.
2024
Addsum HR Solutions begins
Dr Doris Li joins as HR partner, bringing a doctorate in Human Resource Management, academic experience in HR and labour law, and senior leadership across global Fortune 500 and Australian listed companies. Her arrival completes Addsum’s evolution into a full-service professional services firm.
2025
Wealth management launched
Addsum establishes its wealth management team, led by Lynn Lin. This new service area broadens the firm’s ability to support clients in more sophisticated wealth-related matters across investment, structuring and intergenerational planning.
Now
The next generation
Kai Xie, is appointed partner after joining as an intern in 2011 – the first partner to have been appointed from within.
The Addsum difference
Built on relationships. Sustained by results.
We measure our success not by the volume of engagements but by the quality of our relationships and the outcomes our clients achieve. Many of the clients who came to us in our earliest years remain with us today. Here’s what makes it work.
Understanding before action
We take the time to understand each client’s circumstances, priorities, values and relationships before we act. That way, whatever we’re working on – accounting, tax, wealth, HR or finance – is always informed by the full picture, not just the immediate issue.
Coordinated across every dimension
Clients work with professionals who understand their complete position – across business, wealth and family. When complexity sits across multiple service lines or jurisdictions, we bring it into alignment rather than treating each element in isolation.
A second layer of judgment
Our role isn’t just to respond to what clients ask. It’s to test assumptions, identify gaps and ask the questions they may not have thought to ask. That way, we ensure decisions aren’t just efficient but genuinely right for the circumstances.
Beyond business
Invested in our community
Addsum’s commitment to community has always run alongside its business growth. In 2014, Cathy Guo was appointed by the Governor of New South Wales to serve on the Ministerial Advisory Council for Multicultural Affairs. From 2020, she joined the board of the Nan Tien Education Foundation. In 2023, she became a board member of the Museum of Chinese Australian History.
The Addsum Foundation, established in 2016, reflects the same conviction: that lasting success carries a responsibility to give back. In 2017, the Foundation donated nearly A$40,000 to homelessness services. In 2025, it served as principal sponsor of the Vegan Run, supporting programmes addressing homelessness and family violence.
Addsum today
The same firm. Thirty years on.
The client base has grown and the service lines have multiplied. However, the instinct that drove Cathy to rent two desks in Ashfield in 1996 – that clients deserved someone who understood both their financial position and their world – has never changed. It’s still the reason clients stay, refer and return, and it’s still the foundation on which everything Addsum does is built.
