The verdict in three sentences
For a 15-person accounting firm in London, a website able to attract SMEs and overseas subsidiaries costs 6,000 to 12,000 GBP in 2026 (about 7,000 to 14,000 EUR). The price gap comes from three building blocks: multilingual pages for international clients, tax calculators (corporation tax, income tax, VAT) and a secure document upload portal handled in line with ICO and UK GDPR requirements. Allow 6 weeks and around 120 GBP per month for maintenance.
What makes an overseas subsidiary get in touch
A finance director at a French, Spanish or US subsidiary setting up in London compares three or four firms online before calling one. They want to understand in 30 seconds your specialisms, indicative fees, command of UK tax and your ability to report to group in their language.
| Website element | Impact on enquiries (2026 estimate) | Indicative cost |
|---|---|---|
| Service pages (formation, audit, payroll, tax, R&D credits) | Essential | Included in core build |
| French or Spanish pages for subsidiaries | +30 to 50 % international enquiries | 700 to 1,400 GBP |
| Transparent fixed-fee pricing page | Higher-quality leads | 300 to 600 GBP |
| Tax calculators (corporation tax, income tax, VAT) | +20 to 35 % time on site, qualified leads | 1,000 to 2,400 GBP |
| Encrypted document upload portal | Differentiation, time saved | 1,200 to 2,600 GBP |
| Online booking | -40 % phone back-and-forth | 250 to 500 GBP |
| Team profiles with ICAEW/ACCA credentials | Trust, regulatory clarity | Included in core build |
2026 price grid in London
For comparison, the same scope in Casablanca costs 25,000 to 60,000 MAD excluding VAT.
| Package | Content | Price | Timeline |
|---|---|---|---|
| Essential | 8 pages, custom design, contact form, local SEO | 6,000 GBP | 4 weeks |
| Growth | 12 pages, 2 calculators, online booking, blog | 9,000 GBP | 5 weeks |
| Premium | 15 pages in 2 languages, 3 calculators, secure portal, blog | 12,000 GBP | 6 weeks |
| Maintenance | Updates, backups, annual tax rate changes | 120 GBP/month | Ongoing |
| Hosting | Secure server, SSL, CDN, UK/EU data residency | 40 to 90 GBP/month | Ongoing |
| Copywriting | Service pages written by a specialist writer | 120 to 200 GBP/page | In parallel |
Maintenance includes updating calculator rates after each Budget, a step often forgotten: a corporation tax calculator showing last year's rates destroys your credibility.
Compliance and portal security
The portal receives accounts, bank statements and payslips, so it must comply with UK GDPR and the firm must be registered with the ICO (the data protection fee starts at 52 GBP per year for small organisations). Plan for file encryption, two-factor authentication for clients, access logging, UK or EU data residency and a defined retention period (for example 6 years for accounting records).
Mini case study
James Whitfield, partner at a 15-person accounting firm in London, chooses the Premium package at 12,000 GBP with 120 GBP maintenance and 70 GBP hosting per month, so 14,280 GBP in year one.
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
The firm bills an average of 650 GBP per month to an SME and 1,800 GBP per month to an overseas subsidiary. If the website brings 3 extra SMEs and 1 subsidiary over the year, starting on average mid-year, that is roughly (3 x 650 + 1,800) x 6 = 22,500 GBP in first-year revenue, then 45,000 GBP in a full year. The portal also saves assistants about 6 hours a week previously spent chasing documents by email.
FAQ
Do we really need a second language?
Only if you target overseas subsidiaries: French or Spanish pages add 700 to 1,400 GBP. For a purely UK SME client base, English alone is enough.
Do tax calculators create liability for the firm?
They must carry a notice that results are indicative and not advice. Rates are updated after each Budget as part of the 120 GBP monthly maintenance.
Is the document portal ICO compliant?
It can be, with encryption, two-factor authentication, UK or EU hosting and a documented retention policy. Expect 1,200 to 2,600 GBP depending on client numbers and features.
How long before we rank on Google in London?
For queries like "accountant for overseas companies London", allow 3 to 6 months to reach page one with 2 blog posts per month. A Google Business Profile often brings first calls within the first month.
Can we start small and add modules later?
Yes, the Essential package at 6,000 GBP can grow into Premium. Adding modules step by step costs about 10 % more than ordering everything at once.
Let's scope your project. Tell us your target languages, the calculators you need and how many clients will use the portal: we will price your website between 6,000 and 12,000 GBP, deliverable in 6 weeks. 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.
