Definition
Cost per lead (CPL) is the amount a law firm spends on advertising to get one qualified contact, such as a completed form or a phone call, calculated by dividing ad spend by the number of leads generated over a given period. It tells you what a new inquiry from a prospective client really costs.
In plain English
CPL is the core metric for judging whether your advertising pays off. Cost per click only measures a visit. CPL measures what you actually pay for a prospective client to get in touch with your firm.
For a law firm, it is the number that lets you compare channels side by side: Google Ads, LinkedIn, or a local campaign such as Local Services Ads. A CPL of $88 means each new qualified contact costs you $88 in ad spend. That figure helps you decide where your budget goes and shift it toward what works.
CPL varies widely by practice area. An employment law lead usually costs less than a mergers and acquisitions lead, because the value of the matter and the level of qualification required are different. LocaliQ's 2026 benchmarks put the average cost per lead for attorneys and legal services at $131.63, the highest of any industry.
For a law firm
A business law firm invests $2,200 a month in paid search on Google Ads. Its landing page generates 18 qualified contact requests in the month. Its CPL is $122 ($2,200 / 18 leads).
The firm then compares that figure with its conversion rate. If 20% of leads become clients with an average fee of $3,850, each new client costs $611 in advertising ($122 × 5). This calculation confirms that the channel is profitable and shows where to adjust bids on the best-performing keywords.
The Hendy figure
Across the law firms we work with, the average Google Ads cost per lead we observed in 2024 ranges from $65 to $200 depending on the practice area, with the low end in family law and the high end in corporate law and intellectual property.
The same budget buys far fewer leads in corporate or IP work than in family law, so each practice area needs its own CPL target.
Key takeaways
- CPL measures what a qualified contact costs, not just a visit to your website
- It varies widely by practice area and by advertising platform
- A high CPL is not necessarily a problem if your conversion rate and your fees justify it