A law firm Google Ads budget should be based on commercial maths, not a generic monthly figure. CPCs vary sharply by practice area, location, device and keyword intent, so broad “average” ranges can be misleading.
Use your own acquisition model
Start with four inputs: expected CPC, landing-page conversion rate, enquiry-to-client rate and average value of an instructed matter.
Clicks = media budget ÷ CPC
Enquiries = clicks × conversion rate
Clients = enquiries × enquiry-to-client rate
This lets you test whether the campaign economics make sense before increasing spend.
Separate practice areas
Do not mix unrelated legal services into one budget model. Family law, immigration, conveyancing, employment and personal injury can have very different search demand and commercial value. Build campaigns and landing pages around distinct practice areas and locations.
Budget for conversion infrastructure too
- Dedicated landing pages
- Call and form tracking
- CRM or lead routing
- Fast follow-up
- Negative keyword management
- Ongoing search-term review
Buying clicks without fixing these areas usually increases waste rather than instructions.
What should you optimise for?
Raw leads are not enough. Track qualified enquiries, booked consultations and instructed matters. A cheaper campaign can still be worse if it attracts the wrong type of case.
Common budgeting mistakes
- Using one budget across every practice area
- Judging performance on CTR instead of matters won
- Ignoring call quality and missed calls
- Sending all traffic to the homepage
- Leaving broad or irrelevant search terms unchecked
- Scaling before conversion tracking is reliable
For the wider law-firm budget picture, see our law firm marketing costs guide.
How much should a small law firm start with?
Use the smallest budget that can generate enough clicks and conversions to produce useful data in the selected market. If the expected click volume is too low to judge performance, either narrow the campaign or accept that the test needs a longer period.
For managed paid search, see our PPC agency for solicitors. For the broader acquisition strategy, read our digital marketing for law firms guide or visit our law firm marketing services hub.
