How to Reduce Law Firm Lock-Up and Get Invoices Paid Faster
A law firm can have plenty of work, report a profit and still struggle for available cash.
Often, the money is simply stuck between doing the work and receiving payment. That delay is known as law firm lock-up, and reducing it can have a direct effect on the amount of cash available for salaries, tax, drawings and investment.
It is also a measure the profession tracks closely. The Law Society’s 2026 Financial Benchmarking Survey — compiled annually by Hazlewoods LLP from over 120 firms across England and Wales — found that total year-end lock-up (WIP and debtors combined) fell to 134 days in 2026, down from 146 the year before. That is still just over four months between completing work and being paid, even after what the survey called a notable improvement. For a firm below the median, that gap represents a genuine drag on cash available for drawings, tax and growth.
What is law firm lock-up?
Lock-up has two main stages.
The first is the period between completing work and issuing the invoice. This is effectively the firm’s WIP cycle.
The second begins once the bill is issued and continues until payment arrives.
Looking only at overdue invoices therefore gives an incomplete picture. A firm with excellent credit control can still experience poor cashflow if work sits unbilled for too long.
Lock-up stage
What it measures
Typical driver
WIP lock-up
Work completed but not yet billed
Late time recording, infrequent billing, slow bill approval
Separating the two matters in practice. A firm that bills promptly but collects slowly needs a different fix to a firm that bills slowly but collects well — and the combined lock-up figure alone won’t tell you which one you have.
Reduce law firm lock-up before the bill is raised
The first opportunity to improve lock-up sits within the billing process.
Time and costs should reach matters promptly. WIP should be reviewed regularly, and billing milestones should be clear.
Waiting until a matter finishes is not always commercially sensible, particularly where work continues for several months. Regular or milestone billing can help the firm convert work into cash progressively rather than funding the full matter from its own resources.
In practice: we recently worked with a five-partner regional practice where WIP had built up to cover close to seven weeks of average monthly billing on longer-running matters. Moving from end-of-matter billing to monthly milestone billing, combined with a weekly WIP review, brought unbilled WIP down by roughly a third within two quarters — without any change in the amount of work being done.
Draft bills should not become another form of WIP
Preparing a draft bill achieves little if it remains unapproved.
Partners should be able to see which bills need attention and how long each has been waiting. A short, focused approval list is usually more useful than another detailed report. The objective is to make the next action obvious and give it an owner.
That principle applies across effective financial management: information should drive action rather than simply describe the problem.
Credit control begins before an invoice is overdue
Good collections do not start with an aggressive overdue letter.
Clear engagement terms, accurate bills and realistic payment expectations all influence whether invoices are paid on time. Once a bill has been issued, the firm should know when payment is due and who will follow up if it does not arrive.
Queries should also be resolved quickly. A genuine billing dispute can remain unpaid for weeks if nobody takes ownership of the response.
Use lock-up as a management measure
Lock-up can reveal problems that headline revenue figures miss.
A team may generate impressive fees but take too long to bill them. Another may bill promptly but struggle to collect. Understanding the difference helps partners focus on the correct intervention.
Comparing your own figure against the sector median is a useful starting point — if total lock-up is meaningfully above 134 days, that’s a signal worth investigating even if revenue looks healthy.
Improving cash without increasing revenue
Reducing law firm lock-up is often one of the most practical ways to strengthen cashflow without asking fee earners to generate more work.
The aim is simple: shorten the path between delivering value and receiving payment.
At AM Strategic, we help firms improve WIP management, billing workflows, credit control and reporting so partners can see where cash is becoming trapped.
1. What does law firm lock-up mean? Lock-up is the period between performing work and receiving payment. It includes both unbilled WIP and unpaid invoices.
2. What is the average lock-up figure for UK law firms? According to the Law Society’s 2026 Financial Benchmarking Survey, total year-end lock-up across participating firms averaged 134 days, down from 146 the previous year. Figures vary significantly by firm size and practice area, so this is a starting benchmark rather than a target.
3. Why does high lock-up cause cashflow pressure? The firm may have earned the revenue but cannot use it until the work is billed and the client pays.
4. How can a law firm reduce WIP lock-up? Regular WIP reviews, prompt time recording, milestone billing and faster bill approval can reduce the time work remains unbilled.
5. How can firms reduce debtor lock-up? Accurate invoices, clear payment terms, prompt follow-up and quick resolution of client queries can all support faster collection.
6. Should Managing Partners monitor lock-up regularly? Yes. Lock-up provides useful insight into how efficiently the firm converts work into cash and can expose problems hidden by revenue figures.
Source: Law Society Financial Benchmarking Survey 2026, produced by Hazlewoods LLP.
Adam Bent is a trusted financial leadership expert with 30 years of experience helping startups and small to medium-sized businesses achieve faster growth. He guides companies to success through strategic financial planning and implementation, using his expertise to build actionable turnaround plans for businesses in financial distress.
Having seen many entrepreneurs with great ideas struggle due to a lack of financial expertise, Adam specialises in translating vision into viable, practical financial models, offering dedicated support every step of the way.
Driven by the reward of seeing businesses thrive, he founded AM Strategic Consultancy to help companies realise their full growth potential.
Adam Bent is licensed and regulated by the AAT under licence number 1005891.
A law firm can have plenty of work, report a profit and still struggle for available cash.
Often, the money is simply stuck between doing the work and receiving payment. That delay is known as law firm lock-up, and reducing it can have a direct effect on the amount of cash available for salaries, tax, drawings and investment.
It is also a measure the profession tracks closely. The Law Society’s 2026 Financial Benchmarking Survey — compiled annually by Hazlewoods LLP from over 120 firms across England and Wales — found that total year-end lock-up (WIP and debtors combined) fell to 134 days in 2026, down from 146 the year before. That is still just over four months between completing work and being paid, even after what the survey called a notable improvement. For a firm below the median, that gap represents a genuine drag on cash available for drawings, tax and growth.
What is law firm lock-up?
Lock-up has two main stages.
The first is the period between completing work and issuing the invoice. This is effectively the firm’s WIP cycle.
The second begins once the bill is issued and continues until payment arrives.
Looking only at overdue invoices therefore gives an incomplete picture. A firm with excellent credit control can still experience poor cashflow if work sits unbilled for too long.
Separating the two matters in practice. A firm that bills promptly but collects slowly needs a different fix to a firm that bills slowly but collects well — and the combined lock-up figure alone won’t tell you which one you have.
Reduce law firm lock-up before the bill is raised
The first opportunity to improve lock-up sits within the billing process.
Time and costs should reach matters promptly. WIP should be reviewed regularly, and billing milestones should be clear.
Waiting until a matter finishes is not always commercially sensible, particularly where work continues for several months. Regular or milestone billing can help the firm convert work into cash progressively rather than funding the full matter from its own resources.
In practice: we recently worked with a five-partner regional practice where WIP had built up to cover close to seven weeks of average monthly billing on longer-running matters. Moving from end-of-matter billing to monthly milestone billing, combined with a weekly WIP review, brought unbilled WIP down by roughly a third within two quarters — without any change in the amount of work being done.
Draft bills should not become another form of WIP
Preparing a draft bill achieves little if it remains unapproved.
Partners should be able to see which bills need attention and how long each has been waiting. A short, focused approval list is usually more useful than another detailed report. The objective is to make the next action obvious and give it an owner.
That principle applies across effective financial management: information should drive action rather than simply describe the problem.
Credit control begins before an invoice is overdue
Good collections do not start with an aggressive overdue letter.
Clear engagement terms, accurate bills and realistic payment expectations all influence whether invoices are paid on time. Once a bill has been issued, the firm should know when payment is due and who will follow up if it does not arrive.
Queries should also be resolved quickly. A genuine billing dispute can remain unpaid for weeks if nobody takes ownership of the response.
Use lock-up as a management measure
Lock-up can reveal problems that headline revenue figures miss.
A team may generate impressive fees but take too long to bill them. Another may bill promptly but struggle to collect. Understanding the difference helps partners focus on the correct intervention.
Comparing your own figure against the sector median is a useful starting point — if total lock-up is meaningfully above 134 days, that’s a signal worth investigating even if revenue looks healthy.
Improving cash without increasing revenue
Reducing law firm lock-up is often one of the most practical ways to strengthen cashflow without asking fee earners to generate more work.
The aim is simple: shorten the path between delivering value and receiving payment.
At AM Strategic, we help firms improve WIP management, billing workflows, credit control and reporting so partners can see where cash is becoming trapped.
If your firm’s revenue looks healthy but too much cash remains tied up in WIP or debtors, book a consultation with AM Strategic to review your lock-up position.
Frequently Asked Questions
1. What does law firm lock-up mean? Lock-up is the period between performing work and receiving payment. It includes both unbilled WIP and unpaid invoices.
2. What is the average lock-up figure for UK law firms? According to the Law Society’s 2026 Financial Benchmarking Survey, total year-end lock-up across participating firms averaged 134 days, down from 146 the previous year. Figures vary significantly by firm size and practice area, so this is a starting benchmark rather than a target.
3. Why does high lock-up cause cashflow pressure? The firm may have earned the revenue but cannot use it until the work is billed and the client pays.
4. How can a law firm reduce WIP lock-up? Regular WIP reviews, prompt time recording, milestone billing and faster bill approval can reduce the time work remains unbilled.
5. How can firms reduce debtor lock-up? Accurate invoices, clear payment terms, prompt follow-up and quick resolution of client queries can all support faster collection.
6. Should Managing Partners monitor lock-up regularly? Yes. Lock-up provides useful insight into how efficiently the firm converts work into cash and can expose problems hidden by revenue figures.
Source: Law Society Financial Benchmarking Survey 2026, produced by Hazlewoods LLP.
Adam Bent is a trusted financial leadership expert with 30 years of experience helping startups and small to medium-sized businesses achieve faster growth. He guides companies to success through strategic financial planning and implementation, using his expertise to build actionable turnaround plans for businesses in financial distress.
Having seen many entrepreneurs with great ideas struggle due to a lack of financial expertise, Adam specialises in translating vision into viable, practical financial models, offering dedicated support every step of the way.
Driven by the reward of seeing businesses thrive, he founded AM Strategic Consultancy to help companies realise their full growth potential.
Adam Bent is licensed and regulated by the AAT under licence number 1005891.