Write-offs are one of the most significant and least discussed sources of financial loss in UK legal practice. A write-off occurs when a firm records time or incurs a disbursement that is never billed to the client — or is billed but later reduced or cancelled. The gap between time recorded and fee income received is known as the realisation rate, and for the average UK firm it sits around 85%. That means for every £1 of time recorded, 15p is lost.

For a firm billing £2 million per year, that is £300,000 in recorded-but-unrecovered value — before bad debts are counted. Understanding where write-offs come from, and systematically reducing them, is one of the highest-return activities available to law firm management.

Understanding Write-Off Categories

Write-Off at Billing (Billing Haircut)

The most common form of write-off happens at billing review. The billing partner reviews the draft invoice, considers whether each item is recoverable given the client relationship and matter type, and reduces or removes items before the invoice goes out. This “billing haircut” often happens invisibly — the write-off never appears on a report; the invoice simply goes out lower than the recorded WIP.

Haircut write-offs have multiple causes:

Poor narratives: entries that do not describe the work adequately are written off because the billing partner cannot justify them to a client who queries the bill
Time considered excessive: the partner judges that particular tasks took longer than a client would accept — even if the time was genuinely spent
Relationship management: the partner applies a discount to maintain goodwill with a valued client
Scope creep: work was done outside the original retainer scope and the firm is reluctant to bill for it without a prior conversation

Haircut write-offs typically account for 50–70% of total firm write-offs.

WIP Write-Offs

WIP write-offs occur when time that was recorded but never billed is formally written off — either at file closure, during an annual WIP review, or when a matter is abandoned. Common triggers:

Aborted transactions: a conveyancing matter that falls through, a corporate deal that collapses, a claim that the client decides not to pursue
Aged WIP over 12 months: time that was never billed and cannot now be justified to the client
Irrecoverable fixed fee overruns: work done in excess of a fixed fee that was never the subject of a scope change agreement

Billing Write-Offs (Credit Notes)

Where an invoice has been issued and the client disputes it, the firm may issue a credit note — a partial or total reversal of the bill. This is a billing write-off. It differs from a haircut because the revenue was recognised, then taken back. The Legal Ombudsman reports that costs disputes resulting in credit notes cost UK firms tens of millions of pounds annually.

Bad Debt Write-Offs

Where a debt has been issued, the recovery process exhausted, and the amount is irrecoverable, it becomes a bad debt write-off. This is a cash loss as well as a revenue loss — the firm has already borne the cost of doing the work. For most firms, bad debt runs at 1–3% of billings. Higher rates usually indicate a credit control failure rather than an unusual level of client financial difficulty.

The Root Causes of Excessive Write-Offs

Inadequate Time Recording

The most fundamental cause of billing haircuts is poor time recording. When narratives are vague, dates inconsistent, or entries appear to duplicate work, the billing partner writes them off rather than risk a client challenge. The fee earner’s incentive is to avoid administrative friction; the billing partner’s is to avoid client conflict. Together, these incentives consistently produce lower invoices than the work justifies.

Contemporaneous recording, specific narratives, and accurate matter allocation are the structural solution. These are disciplines, not technology problems — though technology helps.

Scope Creep Without Communication

When a matter runs over its original estimate — whether fixed fee or hourly — without the client being told, the billing partner faces an invidious choice: bill the full amount and face a dispute, or write it off and absorb the loss. Neither outcome is good. The cause is always a failure to communicate scope change at the time it happened.

The solution is a firm culture where fee earners are required to update clients when scope changes materially, with confirmation in writing. This is an SRA obligation (Paragraph 8.7 of the SRA Code of Conduct requires you to keep clients informed about costs) as well as a commercial necessity.

Billing Delay

The longer the gap between doing the work and issuing the invoice, the more likely the bill is to be written off. The billing partner reviewing a six-month-old time entry for a matter that concluded in March has little recollection of the detail and tends to doubt its recoverability. The client who receives an invoice in October for work done in April will challenge it.

Prompt billing — ideally monthly, or at matter completion within 30 days — dramatically reduces haircut write-offs. WIP over 90 days old is consistently written off at higher rates than fresh WIP.

Lack of Billing Partner Oversight

In some firms, write-off decisions are made inconsistently — one partner writes everything off to maintain client relationships; another bills everything and faces disputes. Without firm-level write-off monitoring and approval processes, there is no feedback loop to identify and correct habitual over-writing.

Fixed Fee Mispricing

Fixed fees that are priced too low generate structural write-offs. A conveyancing fee that was right in 2019 may be materially inadequate by 2024 given changes in the complexity of transactions, AML requirements, and leasehold reform compliance. Firms that review fixed fee pricing annually and adjust for scope drift have significantly lower write-off rates on fixed-fee work.

Practical Strategies for Reducing Write-Offs

Establish a Write-Off Approval Process

No write-off above a defined threshold (£250 is typical in mid-size firms; £500 in larger practices) should happen without a formal approval by the billing partner and, above a higher threshold, a practice manager or managing partner.

Write-off approvals should be recorded with a reason code. Typical reason codes:

N1: Time exceeded reasonable estimate — not communicated to client
N2: Poor narrative — billing partner unable to justify entry
N3: Work outside agreed scope — scope change not agreed
N4: Relationship discount
N5: Aborted matter — WIP not recoverable
N6: Duplicate entry

The reason codes generate a monthly write-off report that identifies patterns. A billing partner with a high N2 rate has a time recording quality problem. A practice area with a high N3 rate has a scope management problem. The data drives the right conversation.

Improve Narrative Quality

Address poor narrative quality directly. Run a training session showing fee earners actual examples of write-offs arising from inadequate narratives versus recovered time with good narratives. Make the financial cost visible.

Set a minimum narrative standard: at least eight words describing the specific work and the issue it addressed. Build a review step into billing preparation: before any invoice goes out, review time entries with narratives under 10 words and either enhance them (if the fee earner can remember the detail) or write them off rather than billling something the client will immediately dispute.

Adopt Milestone Billing on Complex Matters

For matters where the total cost is uncertain — litigation, corporate transactions, complex planning applications — agree milestone billing at the outset. Bill at each milestone rather than at completion. This prevents WIP accumulating to irrecoverable levels and ensures the client is regularly updated on costs.

Milestone billing also surfaces scope issues early. If the client pushes back at the interim invoice because costs are higher than expected, that is the right time to have the conversation — not at final invoice when the work is done and the WIP write-off is the only remaining option.

Review Fixed Fee Structures Annually

Conduct an annual fixed fee profitability review. For each fixed fee service:

Calculate the average time actually recorded per matter
Apply the relevant hourly rate to get an average cost
Compare to the fixed fee charged
Calculate the average write-off per matter

Where the write-off per matter exceeds 10%, either the fixed fee needs to increase, the scope needs to narrow, or the process needs to become more efficient. Publishing the results of this review — even informally — generates productive discussions about pricing and process.

Front-Load Client Costs Communication

Write-offs related to scope creep and billing dispute are most often preventable. Firms that invest in excellent up-front costs communication — specific estimates, clear scope limits, defined billing triggers — have materially lower write-off rates.

A client who has been told that the matter is likely to cost £8,000–£12,000 and who receives an invoice for £9,500 is unlikely to dispute it. A client who was told “approximately £5,000–£6,000” and receives £9,500 is almost certain to.

Train fee earners to give specific, staged estimates and to update them promptly when scope changes. This is uncomfortable but far less uncomfortable than writing off £3,000 or receiving a Legal Ombudsman complaint.

Reduce Billing Cycles

Move from quarterly to monthly billing. Move from completion-billing on long matters to interim billing at milestones. Every reduction in billing cycle length reduces WIP accumulation, reduces the haircut applied to aged entries, and reduces the billing dispute rate.

Firms that switch from quarterly to monthly billing consistently report 10–15% improvements in billing realisation within six months.

Managing Write-Offs When They Are Unavoidable

Aborted Transactions

Not every write-off is preventable. A conveyancing transaction that falls through at exchange has cost the firm time that cannot be recovered from the client unless the engagement letter provides for it. Ensure your engagement letters include an abortive work clause that specifies the basis on which you will charge if the matter does not complete.

Standard abortive charge provisions allow you to charge on a time-spent basis (or a fixed portion of the completion fee, e.g. 50–75%) if the matter aborts through no fault of the solicitor. Clients who sign the engagement letter with this provision have agreed to it; few disputes arise.

Client-Funded Write-Offs

Where a client requests additional work that turns out to be unnecessary — for example, commissioning an expert report that does not assist the case — consider whether the write-off should be shared. A frank conversation with the client — “we instructed this expert at your request, and the report has not assisted us, so we are writing off 50% of the fee” — can result in partial recovery and preserves the relationship better than a full invoice or a full write-off.

Write-Off Reports and Monitoring

Produce and review a monthly write-off report at partner level. The report should show:

Total write-offs by amount and as a percentage of recorded WIP
Write-offs by fee earner (to identify performance issues)
Write-offs by reason code (to identify systematic causes)
Write-offs by practice area (to identify structural pricing issues)
Trend over time (to measure whether interventions are working)

Partners who understand their write-off rate — and who see it benchmarked against their colleagues — are more motivated to improve than those who have no visibility of the data.

How Obiter Reduces Write-Offs

The most common causes of write-offs — poor narratives, unrecorded time, and billing delay — are problems that better time recording directly solves. Obiter automatically generates time entries from fee earner activity, with narratives specific enough to survive billing review, and presents them for approval in real time rather than at month end. The result is fewer haircuts, fewer WIP ageing problems, and a billing run that takes hours rather than days. Firms using Obiter consistently see their realisation rates move toward 90–95% within the first quarter of use.

Summary

Write-offs are largely a management problem, not a market problem. The firms with the lowest write-off rates are not the ones with the easiest clients or the simplest work — they are the ones with the best time recording, the clearest costs communication, the most consistent billing processes, and the management reporting to identify and correct failure. Every percentage point improvement in realisation rate drops directly to the bottom line.

Reducing Write-Offs at Your Law Firm: Causes and Solutions