The verdict in three sentences
For a firm of 18 lawyers, an off-the-shelf SaaS at 50 to 120 EUR per user per month covers case management, diary and standard billing very well. Custom software, at 35,000 to 90,000 EUR excluding VAT (2026 order of magnitude, about 30,000 to 77,000 GBP), becomes relevant when your time recording, fee arrangements or client reporting no longer fit a generic tool. The deciding question is how many billable hours you lose every month because time is not recorded reliably.
What law firm software must cover in 2026
A London firm handling corporate, employment and litigation work juggles three flows: matters and their documents, time recorded per fee earner, billing and collections. Add electronic filing with the courts through CE-File, the SRA Accounts Rules on client money, and the growing push for structured electronic invoices from corporate clients.
| Feature | Off-the-shelf SaaS | Custom | Watch point |
|---|---|---|---|
| Matter record, parties, conflict checks | Yes, standard | Yes, with your own check rules | Conflicts across related companies |
| Time recording | Timer and manual entry | Capture from diary, emails and documents | Actual recording rate of partners |
| Fee arrangements | Generic templates | Fixed fee, hourly, success fee combined | Client care letter requirements |
| Billing and chasers | Yes | Yes, with client reporting by matter | E-billing formats (LEDES) for corporate clients |
| Court e-filing | Depends on vendor, sometimes optional | Integrated with existing tools | CE-File and HMCTS portals |
| Document management | Stored with the vendor | Hosting of your choice | Legal privilege, UK hosting |
| Partner dashboards | Standard | Profitability by matter, client, fee earner | Real margin on fixed fees |
Legal professional privilege and UK GDPR call for careful hosting: encryption, access logs, servers in the UK or EU, and a reversibility clause that lets you recover matters and documents if you switch tools.
SaaS or custom: the five-year calculation
Assumptions: 24 users (18 lawyers and 6 assistants or paralegals), SaaS at 85 EUR per user per month, custom development at 60,000 EUR with 9,000 EUR of maintenance and hosting a year.
| Item | Off-the-shelf SaaS | Custom |
|---|---|---|
| Setup and data migration | 3,000 to 8,000 EUR | Included in the project |
| Upfront cost | 0 EUR | 35,000 to 90,000 EUR |
| Annual cost | 24,480 EUR | 9,000 EUR |
| Cumulative over 3 years | 76,440 EUR | 87,000 EUR |
| Cumulative over 5 years | 125,400 EUR | 105,000 EUR |
| Time to go live | 1 to 2 months | 4 to 6 months |
| Ownership of code and data | No | Yes |
On licences alone, the gap only becomes clear from year four. The decisive argument for custom lies elsewhere: recovered billable time and a fit with how you bill. A firm that mostly bills fixed fees does not have the same needs as a litigation practice billing by the hour.
A custom project in 4 to 6 months
| Phase | Duration | Deliverable |
|---|---|---|
| Scoping with partners and assistants | 3 weeks | Flow mapping, mock-ups |
| Matters, conflicts and documents | 5 to 6 weeks | Matter record, document management, access rights |
| Time and billing | 5 to 6 weeks | Recording, fee arrangements, e-invoices |
| Court e-filing, email, accounting links | 3 to 4 weeks | Exchanges with existing tools |
| Data migration and acceptance | 3 weeks | Import of live matters, training |
Practical advice: have two partners and two associates test time recording from week six. It is the feature that drives adoption, and therefore return on investment.
Mini case study
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James, partner at an 18-lawyer firm in London (illustrative persona), sees that each lawyer forgets on average 20 minutes of billable time a day. Over 200 working days, that is 18 x 0.33 h x 200 = about 1,200 hours a year. If a suitable tool recovers 40 %, or 480 hours, at an average hourly rate of 350 EUR (about 300 GBP), the potential gain reaches 168,000 EUR a year, even before discounts granted to clients. Against a 60,000 EUR project and 9,000 EUR of annual maintenance, payback is counted in months. Conversely, if the recording rate is already good, a well configured SaaS remains the more reasonable choice.
FAQ
Can custom software connect to court e-filing?
Yes, by relying on official HMCTS portals and filing receipts imported into matters. Allow 2 to 4 weeks of integration and testing depending on your setup.
Where should a law firm's data be hosted?
No sector certification is mandatory, but privilege and UK GDPR justify UK or EU hosting, encrypted, with access logs. Allow 150 to 600 EUR a month depending on document volume.
How much does a SaaS cost for 24 users?
Between 1,200 and 2,900 EUR a month depending on the vendor and modules, or 14,400 to 34,600 EUR a year. Advanced document management and e-signature modules are often billed on top.
Do the SRA Accounts Rules change the choice?
Yes: client money must be ledgered separately and reconciled at least every five weeks. Whatever the option, the tool must produce these reconciliations or feed a compliant accounts system.
Can SaaS and custom be combined?
It is often the best option: keep a SaaS for the matter and diary core, and build a time recording and client reporting module for 20,000 to 40,000 EUR.
Let's scope your project. Tell us your number of users, how you bill and your current tools: we will price a scope, an indicative budget and a go-live schedule. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
