The verdict in three sentences
A serious B2B e-commerce platform costs between 30,000 and 65,000 EUR in 2026, depending on pricing complexity, customer accounts and integrations. The line item that blows the budget is almost never the catalog: it is ERP/stock integration and per-customer pricing logic. Plan for 12 to 20 weeks and think in 5-year TCO, not purchase price.
The cost line items of a B2B project
B2B is not B2C with a "pro" checkbox. You must handle negotiated prices, multi-user accounts, quotas, purchase orders and often a customer credit line. Each brick has a cost.
| Line item | 2026 range (EUR) | What drives it |
|---|---|---|
| B2B platform (core + catalog) | 20,000 - 45,000 | SKU count, variants, languages |
| Per-customer pricing + quotas + grids | 6,000 | Price rules, volume discounts, contracts |
| ERP / real-time stock integration | 6,000 - 12,000 | API availability, mapping complexity |
| Payments + credit terms handling | 4,000 | Bank transfer, installments, credit limits |
| Multi-user customer accounts | 3,000 - 5,000 | Roles, approval workflow |
| Project total | 30,000 - 65,000 | Real scope validated in workshop |
A credible quote itemizes these lines. A 15,000 EUR "all-inclusive" quote hides either a hacked B2C template or surprises during integration.
SaaS vs custom: the 5-year TCO
Purchase price is misleading. Over five years, subscriptions and commissions weigh as much as the initial build.
| Option | Initial build | Annual recurring | 5-year TCO (order of magnitude) |
|---|---|---|---|
| Shopify Plus B2B | 15,000 - 30,000 | ~28,000 (plan + apps) | 155,000 - 170,000 |
| Adobe Commerce | 60,000 - 150,000 | 20,000 - 40,000 | 160,000 - 350,000 |
| Custom (Next.js + ERP) | 40,000 - 100,000 | 8,000 - 15,000 (hosting + maintenance) | 80,000 - 175,000 |
Custom pays off when your B2B rules are too specific for a SaaS, or when volume makes commissions explode. Below 2M EUR of online GMV, a SaaS is often the best risk/cost ratio.
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
Mini case study
Marc, sales director of an industrial supplies wholesaler in Lille, serves 320 business customers with negotiated pricing. Chosen quote: 48,000 EUR, of which 11,000 for the Sage ERP integration. Before, 4 reps keyed in 60 orders/day by phone. After go-live, 45% of orders move to self-service, freeing up 1.5 FTE (about 55,000 EUR/year). Payback in 11 months, excluding average order value gains.
FAQ
Why does a B2B platform cost more than a B2C site? Because you must code per-customer pricing, multi-user accounts and ERP integration. Those three bricks often represent 40 to 50% of the budget.
Can I start small then expand? Yes. A 25,000 EUR core with customer pricing and payments, then ERP in phase 2, is a sound approach that spreads the investment over 6 to 9 months.
How much is annual maintenance? Budget 8 to 15% of the initial build per year for custom, or the platform subscription (from ~2,300 EUR/month for Shopify Plus B2B in 2026).
What is a realistic timeline? 12 to 20 weeks for a first production version, ERP integration included. A quoted 6-week timeline almost always hides a trimmed scope.
Do I need to rebuild my ERP? No, in 90% of cases we connect via API. The cost depends on the quality of existing APIs, not their age.
Let's scope your project. Tell us your number of business customers, your pricing complexity and your current ERP: we will price the exact scope and 5-year TCO. 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.