The verdict in three sentences
Migrating an 8,000-page institutional site from an ageing Drupal to Next.js costs between 40,000 and 95,000 EUR (net) over 12 to 18 weeks. The cost is not in the front end but in content migration, the redirect plan and multilingual reprocessing. A botched migration can cost 30 % of organic traffic; that is the item to secure first.
Detailed budget by workstream
An institutional project is run like a construction site. Here is the 2026 order of magnitude for 8,000 pages in two languages.
| Workstream | Scope | 2026 cost (EUR net) | Timeline |
|---|---|---|---|
| Existing content audit | Mapping 8,000 pages, triage, obsolete | 6,000 - 12,000 | 2 - 3 wks |
| Redirect plan | 301 URL mapping, orphan handling | 4,000 - 8,000 | 1 - 2 wks |
| Structured data migration | Scripts, taxonomies, media, metadata | 10,000 - 22,000 | 3 - 5 wks |
| Next.js front + design | Design system, templates, AA accessibility | 14,000 - 35,000 | 5 - 7 wks |
| Multilingual reprocessing | EN/DE, hreflang, editorial workflow | 4,000 - 12,000 | 2 - 3 wks |
| QA & cutover | Testing, editorial freeze, go-live | 2,000 - 6,000 | 1 - 2 wks |
| Total | Full project | 40,000 - 95,000 | 12 - 18 wks |
Structured data migration is the riskiest item: badly re-imported taxonomies and lost metadata are the classic causes of overrun.
Quantified watch points
An institutional project has constraints marketing sites do not. Here are the items to scope.
| Item | Stakes | 2026 order of magnitude |
|---|---|---|
| Editorial freeze | No-publish window during cutover | 5 - 15 days |
| 301 redirects | SEO preservation of 8,000 URLs | 100 % mandatory |
| WCAG accessibility | AA compliance, audit included | 4,000 - 9,000 EUR net |
| Post-migration maintenance | Annual support | 12,000 - 24,000 EUR net/yr |
| Tolerable traffic loss | Target | < 5 % at 3 months |
| Editor training | Onboarding to the new CMS | 2 - 5 days |
The editorial freeze must be negotiated early with the communications teams: it is often the number one organisational friction point.
Mini case study
Ms Keller, CIO of a public institution in Berlin, must migrate an end-of-life Drupal 7 with 8,200 bilingual pages. Keeping the obsolete Drupal costs her 26,000 EUR (net)/year in extended security support. She invests 72,000 EUR (net) in a Next.js migration over 16 weeks, with a full redirect plan and an accessibility audit. Post-migration maintenance drops to 18,000 EUR (net)/year, saving 8,000 EUR a year, and traffic loss stays under 4 % at three months. The project pays back on security support alone in a little over nine years, but accessibility compliance and the end of the Drupal risk justify the decision on their own.
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FAQ
Why does migrating cost more than a new marketing site?
Because the value is in the 8,000 existing pages. Re-importing that content, its taxonomies and its URLs without loss takes more engineering than starting from a blank page.
How long does the editorial freeze last?
Between 5 and 15 days depending on volume. It can be shortened with an incremental migration, but that slightly lengthens the overall timeline.
How do you guarantee SEO preservation?
With a 301 redirect plan covering 100 % of URLs, tested before go-live. The realistic target is a traffic loss below 5 % at three months.
Is WCAG accessibility mandatory?
For a public institution, yes. Plan 4,000 to 9,000 EUR (net) for the audit and fixes to reach the AA level.
What maintenance budget after migration?
Between 12,000 and 24,000 EUR (net)/year for institutional support covering security, upgrades, accessibility and routine changes.
Let's scope your project. Tell us your page volume, languages and accessibility requirements, and we'll frame your Drupal to Next.js migration. 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.
