Growing a bookkeeping business is exciting.
Those first few clients feel like huge wins. Then another arrives through a referral. Then another.
Before long, your calendar is full and your client list looks healthy.
From the outside, everything appears to be working.
But there is a risk many Bookkeepers don’t notice until something changes.
And it is often hiding in plain sight.
What is client concentration risk in bookkeeping?
Client concentration risk occurs when a large percentage of a Bookkeeper’s income comes from one or two clients.
If one of those clients leaves, sells their business, or brings the work in-house, it can create a sudden loss of revenue.
For many Bookkeepers, this type of bookkeeping client risk develops gradually as successful clients grow and require more support.
The safest bookkeeping businesses spread their revenue across multiple clients to maintain stability.
The story most Bookkeepers recognise
Within the NZQBA community we see this situation quite often.
A Bookkeeper builds a solid client base over time. Through referrals and reputation, new clients arrive steadily.
Eventually one or two clients become larger than the rest. They may have multiple entities, employ more staff, or require more complex reporting.
Naturally, more work flows their way.
They become the client you spend the most time with each month.
At first, this feels like success.
And in many ways, it is.
Until something changes.
Perhaps the business is sold.
Perhaps they hire an internal finance manager.
Perhaps their accountant brings the work into their own firm.
Suddenly a significant portion of your monthly revenue disappears.
This is known as client concentration risk, and it is one of the most common forms of bookkeeping client risk.
Why managing bookkeeping client risk matters for your business
When a small number of clients represent a large percentage of your income, your business becomes more vulnerable than it appears.
This is not about client loyalty. Many clients remain with their Bookkeeper for years.
But businesses evolve. Owners retire. Companies restructure. Technology changes how work is done.
If too much revenue sits with too few clients, even one change can create a noticeable gap in your income.
For many Bookkeepers, this risk develops slowly and unintentionally.
You simply keep saying yes to good work.
Signs your bookkeeping client list may carry hidden risk
A quick review of your client list can reveal a lot.
You may want to take a closer look if:
- One client represents more than 20–30% of your revenue
- A small number of clients take up most of your working hours
- Losing one client would significantly affect your income
- Most of your work comes from a single industry
None of these situations automatically mean there is a problem.
But they are useful signals to monitor.
Understanding your bookkeeping client risk helps you make more informed decisions about how your business grows.
The lesson: healthy businesses spread their risk
Just like the businesses we support, bookkeeping businesses benefit from diversification.
A balanced client list spreads revenue across several clients and industries.
This does not mean avoiding larger clients altogether. Many Bookkeepers enjoy working with growing businesses and complex clients.
The goal is simply to ensure your business does not rely too heavily on one relationship.
When your income is spread across multiple clients, your business becomes far more stable.
How Bookkeepers can reduce client concentration risk
Reducing bookkeeping client risk rarely requires major change.
Often it simply means being more intentional about how your business develops.
You might consider:
- Gradually adding smaller clients alongside larger ones
- Expanding into different industries
- Reviewing your pricing structure to ensure value is spread appropriately
- Maintaining a small pipeline of potential clients through referrals or networking
Even small adjustments can strengthen the stability of your bookkeeping business.
As many experienced Bookkeepers discover, a balanced client list often leads to a more balanced workload as well.
A simple exercise to review your client risk
If you are curious about your own situation, try this quick exercise.
List your current clients and estimate the percentage of revenue each one contributes to your business.
Then ask yourself one simple question:
What would happen if my largest client left tomorrow?
For many Bookkeepers, this exercise brings helpful clarity.
It is not about expecting the worst. It is about understanding the structure of your business.
Building a stronger and more resilient bookkeeping business
The most sustainable bookkeeping businesses rarely rely heavily on one or two clients.
Instead, they grow steadily, build strong relationships, and spread their work across a range of clients.
This creates stability for the Bookkeeper and confidence for the future.
It also allows you to make decisions based on what works best for your business, rather than feeling dependent on any single client.
As your business grows, you may also reach a point where you need additional support. If you are thinking about how to scale your business or share workload more effectively, our Hiring Contractors vs Staff course explores practical options for Bookkeepers expanding their businesses.
You can also explore our guide to starting a bookkeeping business in New Zealand, which includes practical advice on attracting and managing clients from the beginning.
How many clients should a Bookkeeper have?
There is no single number. Most successful Bookkeepers spread their revenue across several clients so their business is not dependent on one or two large accounts.
Is it risky to rely on one large client?
Yes. If one client represents a large percentage of income, losing that client can significantly affect your bookkeeping business.
How can Bookkeepers reduce client concentration risk?
Bookkeepers can reduce risk by gradually adding new clients, working across multiple industries, and reviewing how their revenue is distributed across their client list.
Want to build a more resilient bookkeeping business?
Many Bookkeepers reach a point where their client list is full, but the business still feels fragile.
Through NZQBA, Bookkeepers gain access to practical training, resources, and a supportive community of professionals across New Zealand.
If you are thinking about how to structure your work, grow sustainably, and build a bookkeeping business that supports you long term, NZQBA is here to help.
