Multi-Site Architecture for a Group and Its Subsidiaries: Cost Guide (2026)

The verdict in three sentences

For a group with 7 subsidiaries, a shared multi-site platform costs EUR 30,000 to 60,000 excl. VAT in 2026, roughly half the price of 7 independent websites billed at EUR 65,000 to 100,000. The real saving builds over time: one codebase, one design system and annual maintenance at 15 to 20% of the build instead of seven separate contracts. Plan for 4 to 6 months, with editor accounts per subsidiary so each one keeps its autonomy.

Three possible architectures, three budgets

A group communications director wants two conflicting things: a shared brand identity that strengthens the parent company, and autonomous websites each subsidiary can run without waiting for headquarters. Three architectures meet this need at very different costs. Figures are a 2026 order of magnitude for a Paris-based group, excl. VAT. For a North African group, the same scope typically lands at DZD 4 to 8 million.

The single site is tempting but quickly frustrates subsidiaries, which each have their own clients, offers and sometimes their own domain name. Independent sites drift apart within two years: seven typefaces, seven security levels, seven hosting invoices. The shared multi-site is usually the best compromise.

The shared design system: where the savings happen

A design system is a library of components (headers, cards, forms, key figure blocks, news pages) designed once and reused across all 7 sites. Each subsidiary keeps its accent colour, logo and content, but the structure is shared. Result: a security patch or accessibility improvement ships everywhere in a single release.

Permissions are the second pillar. Each subsidiary gets editor accounts limited to its own site, with an approval workflow: writer, subsidiary communications lead, then group approval for sensitive content such as financial press releases. If Arabic or another right-to-left language is needed, it must be planned from the mockups, not bolted on at the end.

A 4 to 6 month schedule

Launching the group site and the most mature subsidiary first validates the platform before opening the other 6.

Mini case study

Karim, communications director of a group with 7 subsidiaries (construction, distribution, food), receives two offers. Option A: 7 independent sites for EUR 80,000, maintenance EUR 16,000 a year. Option B: shared multi-site for EUR 47,000, maintenance at 18%, so EUR 8,460 a year. Over 3 years, A costs 80,000 + 3 × 16,000 = EUR 128,000, B costs 47,000 + 3 × 8,460 = EUR 72,380. Saving: EUR 55,620 over 3 years, about 43%, with a brand that is finally consistent.

FAQ

How much does a multi-site platform cost for a 7-subsidiary group?

Between EUR 30,000 and 60,000 excl. VAT in 2026 depending on languages, integrations and content volume to migrate. Annual maintenance is 15 to 20% of that amount.

Can each subsidiary keep its own domain name?

Yes, a multi-site platform runs several domains on one infrastructure. Each subsidiary keeps its address and search rankings, with no significant extra development cost.

Can the platform handle right-to-left languages such as Arabic?

Yes, provided right-to-left layout is planned in the design system. Adding it afterwards can cost 15 to 25% of the initial development budget.

What happens if a subsidiary is sold?

Its site can be extracted and handed over with its content in 2 to 4 weeks. This should be written into the contract, with a documented export.

Why 4 to 6 months and not 2?

The technical platform takes 2 to 3 months, but collecting content from 7 subsidiaries and group approvals stretch the schedule. A subsidiary-by-subsidiary rollout limits that risk.

Let's scope your project. Tell us how many subsidiaries, which languages and your current sites: we will price a multi-site architecture between EUR 30,000 and 60,000 excl. VAT, delivered in 4 to 6 months. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.