B2B e-commerce platform build cost for a wholesaler in London (2026)

The verdict in three sentences

A B2B portal is not a consumer store with a login: it is an engine for per-customer negotiated pricing, credit limits and recurring orders wired into your ERP. In 2026, budget 40,000 to 120,000 EUR depending on the number of pricing rules and the depth of integration, plus 300 to 900 EUR/month to run. The return shows up in average order value and freed-up sales time, not in visitor counts.

What separates a B2B portal from a B2C site

The price gap comes from business rules that are invisible on screen but heavy to build. A B2B catalogue shows a different price per logged-in customer, hides off-contract products and enforces minimum quantities.

Every row is developer-days of work: that is why a B2B portal costs 3 to 5 times a showcase e-commerce site.

Custom build or packaged solution

Two routes exist in 2026: a B2B SaaS solution (Shopify B2B, BigCommerce B2B) that you configure, or a custom build. The choice depends on the complexity of your pricing rules.

Rule of thumb: under 500 SKUs with standard pricing rules, the packaged solution wins. Beyond that, or if your prices depend on multi-criteria contracts, custom becomes cost-effective.

ROI shows up in average order value

A well-built portal increases order frequency and size because customers order 24/7 without a salesperson.

These 2026 orders of magnitude are estimates: a wholesaler with 150 active customers often recoups the portal cost within 12 to 18 months.

Mini case study

Thomas runs a catering-supplies wholesaler in London with 210 trade customers and 3 salespeople. Each phone order takes 12 minutes of back-office time. He invests 72,000 EUR in a custom portal with negotiated pricing and payment terms.

After 6 months, 60% of orders come in online. Across 4,200 orders/year, that is 2,520 automated orders, saving about 504 hours of back-office work (2,520 x 12 min). At 28 EUR/hour loaded cost, annual savings reach 14,100 EUR, on top of a 27% higher average order value. Projected payback: around 16 months.

FAQ

What does a B2B portal really cost in 2026?

Between 40,000 and 120,000 EUR for a custom build, depending on the number of pricing rules and ERP integration complexity. A configured packaged solution drops to 15,000-45,000 EUR but with a higher monthly subscription.

Do I have to connect my ERP?

For a true B2B portal, yes: without synced stock, pricing and invoices, your teams re-key everything and errors spike. It is the most structural line item, often 25 to 40% of the budget.

How long to go live?

Allow 4 to 8 months for custom, 6 to 12 weeks for a packaged solution. The timeline depends mostly on your product-data quality and your ERP API availability.

Can payment terms be managed online?

Yes: the portal applies a per-customer credit ceiling, automatically blocks orders that exceed it and issues the invoice at 30 or 60 days. It is a standard B2B function but must be coded correctly.

Can I start small then extend?

Yes. Many wholesalers launch an MVP at 40,000-50,000 EUR (catalogue, per-customer pricing, ordering) then add credit limits, quick reorder and connectors in batches. It is the healthiest strategy for cash flow.

Let's scope your project. Tell us your number of trade customers, your pricing rules and your current ERP, and we'll price an MVP portal plus its extensions. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.