Client portal development cost in London for 2026

The verdict in three sentences

A custom client portal in London in 2026 ranges from 25,000 to 80,000 EUR depending on modules, over a 3 to 6 month timeline. Budget an extra 200 to 800 EUR/month for hosting and infrastructure, plus maintenance of 12 to 18% of the build cost per year. Custom pays off only when the portal durably cuts emails, calls and admin time — not before.

How much a client portal costs in 2026

Price depends mainly on the number of modules and the required security level. Here are the ranges seen on the London market (2026 order of magnitude, mid-sized agencies and studios).

The most underestimated line is integrations (ERP, CRM, accounting tools): a single clean connection often costs 4,000 to 9,000 EUR on its own.

Recurring costs: the real 3-year budget

The build price is only the first line. A portal lives, updates and needs securing. Here is the recurring cost structure.

For a Standard portal at 50,000 EUR, expect a total cost of ownership of around 70,000 to 85,000 EUR over 3 years, hosting and maintenance included.

Mini case study

Claire, CFO of a 45-person consulting SME in London, handles 600 invoices and 300 client files a year. Her teams spend around 22 hours/week emailing documents and invoices and answering follow-ups. A Standard portal at 48,000 EUR automates document access and case tracking. By removing 60% of these tasks, she saves ~13 hours/week, nearly 620 hours/year. At a loaded cost of 35 EUR/h, that is ~21,700 EUR/year of recovered time: the portal pays back in a little over two years, before counting improved client satisfaction and retention.

FAQ

How long does a client portal take to deliver?

Expect 3 to 6 months depending on scope. A working MVP (auth + documents + invoices) can ship in 3 to 4 months, then grow through 3 to 6 week iterations.

Is a custom portal more expensive than a SaaS?

Upfront, yes, but a SaaS at 30 EUR/user/month quickly reaches 15,000 to 40,000 EUR/year at scale. Custom becomes competitive from 40 to 80 active users, especially if your business is specific.

What maintenance costs should I plan for?

Maintenance of 12 to 18% of the build cost per year covers fixes, security and version upgrades. On a 50,000 EUR build, that is 6,000 to 9,000 EUR/year.

Can the portal connect to our ERP or CRM?

Yes, that is common. Each clean integration costs 4,000 to 9,000 EUR depending on the available API. Plan a technical audit upfront to avoid surprises.

How do you secure client data?

Strong authentication, encryption, granular roles, logging and GDPR compliance are the baseline. A security audit costs 3,000 to 8,000 EUR and is justified as soon as you store sensitive documents.

Let's scope your project. Tell us your target modules (documents, invoices, messaging, integrations) and indicative budget; we will scope the perimeter and work packages. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.