The verdict in three sentences
Migrating a heavy Magento to a headless Next.js front + commerce back costs, in 2026, between 40,000 and 120,000 EUR and takes 4 to 8 months. Performance leaps: load time cut by 2 to 3x (LCP under 1.5s), with +10 to 20% conversion. Infrastructure and maintenance costs fall by 30 to 50% — provided a rigorous redirect plan preserves SEO.
Migration budget by scope
The cost depends on catalog richness, the number of integrations and the level of front-end customization. A migration is not a simple re-skin.
| Scope | 2026 budget (EUR) | Timeline | Key content |
|---|---|---|---|
| Simple headless front migration | 40,000 – 60,000 | 4 months | Next.js front, catalog, cart, checkout, redirects |
| Standard migration | 60,000 – 90,000 | 5 – 6 months | + ERP/PIM integrations, i18n, advanced SEO |
| Complex migration | 90,000 – 120,000 | 6 – 8 months | Multi-store, B2B, omnichannel, deep customization |
| Post-migration maintenance | 1,500 – 4,000 / month | — | Support, enhancements, monitoring |
The underestimated line item is almost always data migration and the 301 redirect plan: a badly redirected catalog can drop organic traffic by 20 to 40%.
Performance and cost gains
Headless separates the front (fast, on CDN) from the commerce back. That's where speed and conversion are won.
| Metric | Monolithic Magento | Headless Next.js | Gain |
|---|---|---|---|
| LCP (load) | 3.5 – 5s | 1.0 – 1.5s | ÷ 2 to 3 |
| Conversion rate | base | + 10 to 20% | speed |
| Monthly infra cost | 1,500 – 4,000 EUR | 800 – 2,000 EUR | − 30 to 50% |
| Maintenance cost | high | moderate | − 30 to 50% |
| Core Web Vitals score | 40 – 60 | 85 – 100 | SEO |
An LCP under 1.5s improves experience, Google ranking and mobile conversion at once — mobile being often the weakest on Magento.
Mini case study
Marc, e-commerce director of a furniture retailer in Toulouse, does 6M EUR/year on a Magento with a 4.2s LCP and 3,200 EUR/month of infra. He invests 85,000 EUR in a headless Next.js migration. LCP drops to 1.3s, conversion rises 14%, i.e. about 840,000 EUR of additional revenue per year. In parallel, infra falls to 1,600 EUR/month, i.e. 19,200 EUR saved per year. The migration is recouped in under 3 months on the conversion gain alone.
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FAQ
How much does a Magento to headless migration cost in 2026?
From 40,000 to 120,000 EUR depending on catalog, integrations and front-end customization. A standard migration sits between 60,000 and 90,000 EUR.
How long does the project take?
Expect 4 to 8 months: 4 months for a simple front migration, up to 8 months for a multi-store B2B omnichannel setup.
Does migration risk hurting SEO?
Yes if the 301 redirect plan is rushed: up to −20 to 40% organic traffic. Done well, SEO holds and improves thanks to Core Web Vitals.
What concrete performance gain?
An LCP cut by 2 to 3x (from 3.5-5s to 1-1.5s) and a Core Web Vitals score rising from 40-60 to 85-100, with +10 to 20% conversion.
Do infra costs really drop?
Yes, by 30 to 50%: a static front on CDN and a lighter commerce back cost far less than scaling a Magento monolith.
Let's scope your project. Share your catalog size, your integrations and your current LCP: we'll price the headless migration, indicative budget 40,000 to 120,000 EUR, delivery in 4 to 8 months. 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.
