Law firm client portal development cost 2026: custom build vs off-the-shelf for London and Dublin firms

The verdict in three sentences

For a 12-lawyer firm in London or Dublin, a custom client portal costs between GBP 22,000 and GBP 52,000 (EUR 25,000 to 60,000) in 2026, delivered in 3 to 5 months. An off-the-shelf SaaS costs GBP 35 to 80 (EUR 40 to 90) per user per month, roughly GBP 5,000 to 11,500 a year for 12 seats, with no control over the client journey. Custom becomes worthwhile once the firm wants to integrate its billing, its document templates and its brand, and recovers 6 to 10 hours a week of email back-and-forth.

What a law firm client portal costs in 2026

Price depends on functional scope. A serious legal portal rests on three building blocks: an encrypted document space, secure messaging and tracking of invoices and money on account. Then come the options that push the bill up: e-signature, appointment booking and integration with the practice management system.

These are 2026 order-of-magnitude figures for a mixed team (project lead, developers, designer). A London agency typically bills GBP 700 to 950 per day, a Dublin agency EUR 650 to 850, and a nearshore French-speaking team EUR 350 to 500, which explains the 30 to 40 % gaps between quotes.

Custom build vs SaaS: the numbers

SaaS tools for law firms (client portals bundled with practice management software, virtual data rooms) can go live within days. Their limits: a generic journey, per-seat pricing that climbs with every hire, and little room to fit your own processes.

For London firms, the SRA Code of Conduct requires client confidentiality and the UK GDPR applies; Dublin firms fall under the Law Society of Ireland guidance and the EU GDPR. Neither mandates a specific hosting certification, but both make end-to-end encryption, two-factor authentication, access logging and a documented retention policy the practical baseline. An external penetration test costs GBP 3,500 to 7,000 and reassures institutional clients.

Requirements to put in the specification

Three points prevent nasty surprises. First, require encryption of files at rest (AES-256) and in transit (TLS 1.3), with keys managed outside the application database. Second, plan granular permissions: a client sees their matters, a partner sees everything, an associate sees assigned matters. Third, ask for a reversibility plan: full export of documents and metadata if you change supplier.

The specification should also quantify volumes: number of active clients (often 150 to 400 for a 12-lawyer firm), average document size and retention period (6 years after the matter closes is common practice in the UK). These figures size the storage, which stays modest: GBP 18 to 50 per month per TB with a UK or EU host.

Mini case study

James, partner at a 12-lawyer commercial firm in London, estimates his teams spend 8 hours a week sending documents, chasing clients and answering "where is my matter?". At an average internal hourly cost of GBP 80 (associates and assistants combined), that is GBP 640 a week, roughly GBP 29,400 a year over 46 working weeks.

The firm chooses a portal at GBP 37,000 (core, billing, matter tracking) plus GBP 350 a month of maintenance. If the portal removes 70 % of those exchanges, the annual gain reaches GBP 20,600, minus GBP 4,200 of maintenance: GBP 16,400 net. The investment pays back in about 27 months, before counting faster fee collection thanks to online payment.

FAQ

Is a client portal mandatory for a law firm?

No, but sending confidential documents by unencrypted email exposes the firm if there is a leak. GDPR fines reach up to 4 % of turnover, and a secure portal costs less than a single publicised incident.

Does a legal portal need specialised hosting?

Only if the firm handles health data at scale, for example in personal injury work. In that case, expect a 15 to 25 % hosting premium, roughly GBP 90 to 180 more per month.

How long does it take to launch the portal?

Allow 3 months for the secure core and 5 months for a full version integrated with practice management software. A 3 to 4 week pilot with 10 to 20 clients is strongly recommended.

Does the firm own the code?

Yes, if the contract assigns the intellectual property rights. Require it in writing, together with delivery of the source code and technical documentation at handover.

What maintenance budget should we plan?

Between GBP 220 and 520 a month for hosting, security updates and a bundle of 2 to 5 hours of improvements. That is 6 to 12 % of the initial cost per year.

Let's scope your project. Send us your firm size, matter volumes and practice management software, and we will price a secure portal with an indicative budget and delivery plan. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.