The 15% Rule: Why Your Lawyer May Have to Pay for Their Own Assessment

Most Australians assume that if they want to challenge a legal bill, they'll need to spend money to do it. Hire someone to review the invoice, pay for a formal assessment, absorb the administrative costs, and hope the reduction they win back is more than what they spent getting there. It sounds like a gamble that rarely pays off.

What most people don't know is that the law has already accounted for this concern. Under the Legal Profession Uniform Law, there is a rule that fundamentally changes the risk calculation for clients who believe they've been overcharged. It's straightforward, and it's powerful. If a costs assessor determines that a law practice's fees should be reduced by 15 per cent or more, the cost of that assessment is payable by the law practice, not the client.

That one rule changes everything.

Why the Rule Exists

The 15% threshold wasn't introduced arbitrarily. It reflects a deliberate policy decision that clients shouldn't be financially penalised for exercising a legitimate right, particularly when the overcharging turns out to be substantial.

Think about the dynamic without this rule. A client receives a bill they believe is too high. To challenge it formally, they would need to fund that challenge themselves, not knowing in advance whether the reduction they receive will cover the cost of pursuing it. For many people, especially those who have already spent significant money on their legal matter, that uncertainty is enough to make them give up before they start.

The 15% rule removes that barrier in cases where the overcharging is meaningful. It sends a clear message: if your lawyer charged you significantly more than they should have, they bear the financial consequence of that being discovered, not you.

What Counts as a Costs Assessment

A costs assessment is a formal process conducted by an independent costs assessor, a qualified legal practitioner appointed to review whether the fees charged by a law practice were fair and reasonable in the circumstances.

The assessor looks at a range of factors: whether the work was actually performed, whether it was necessary, whether it was carried out at an appropriate level (meaning it wasn't senior partner time when a paralegal could have handled it), whether the rates charged were consistent with what was disclosed at the outset, and whether the overall fee is proportionate to the complexity and outcome of the matter.

It is not a rubber stamp. Assessors can and do reduce fees, sometimes substantially, and the 15% threshold is reached more often than most clients would expect.

The process applies to a wide range of legal matters: property transactions, family law, commercial disputes, estate administration, personal injury claims, and more. If a lawyer charged you for their services under the Legal Profession Uniform Law, which covers New South Wales, Victoria, and Western Australia, the costs assessment pathway is available to you.

The Practical Difference This Makes

Consider a straightforward example. A client completes a contested family law matter and receives a final bill for $40,000. They feel uneasy about some of the charges but assume that challenging it would cost them money they don't have.

With the 15% rule in mind, the calculation looks different. If a costs assessor reduces that bill by $6,000 or more (which is 15 per cent of $40,000), the law practice pays the assessment costs. The client receives the reduction and is not out of pocket for having pursued it.

Even if the reduction falls below 15 per cent, the client still walks away with a lower bill. The only scenario where they bear the assessment costs is one where the law practice's fees are found to be largely reasonable. And in that case, they at least have the certainty of knowing they were treated fairly.

For clients who have been meaningfully overcharged, the rule is genuinely protective. It means that pursuing a legitimate concern is not a financial risk in the way most people assume.

You Need to Act Within the Time Limits

There is an important caveat to all of this, and it's one that catches people out regularly. Time limits apply to costs assessment applications, and they are strict.

In most circumstances, an application must be made within 12 months of receiving the bill, or 12 months from when the costs were paid, whichever is later. Courts do have some discretion to extend this period in exceptional circumstances, but relying on that discretion is not a strategy. Once the window closes, the right to seek an assessment is generally lost, regardless of how strong the underlying concern might have been.

This is why it matters to act quickly if you have doubts about a legal bill. The instinct to put it aside and deal with it later, which is understandable given how draining most legal matters are, can end up costing you the right to challenge it at all.

Finding Out Whether You Have a Case

Not every legal bill warrants a formal assessment. Some fees, even if they feel high, are within a reasonable range for the work performed. The first step is understanding whether the charges you received are actually out of line, and that requires a review by a costs lawyer who knows what to look for.

At Law in Check, we assess legal bills on behalf of clients and provide clear, honest advice about whether a challenge is likely to be worthwhile. That initial review is free. If we believe your fees are excessive and a formal assessment is appropriate, we'll tell you exactly what that process involves and what you stand to recover.

The 15% rule exists to protect you. Knowing about it is the first step to using it.