B2B web application guide
B2B web application for companies in Spain: when and how to build it
Published: February 20, 2026
A B2B web application is any browser-accessible application serving enterprise clients, partners, distributors, or internal teams with controlled access. It is the type of software that generates the highest ROI at mid-sized companies because it digitises relational processes that previously required calls, emails, and shared spreadsheets.
Most common B2B web application types in Spain
- Client portal: client access to their information (orders, invoices, service status, documentation) with independent authentication separate from the internal system.
- Distributor platform: distributor or franchise network managing their orders, checking real-time stock, and accessing marketing and training materials.
- Supplier extranet: suppliers viewing pending invoices, validating delivery notes, uploading documentation, and communicating with the purchasing team without ERP access.
- Internal team tool: operational management applications for teams without ERP access, or for processes the ERP cannot model — field engineers, sales reps, support teams.
Key features of a well-built B2B application
- Secure multi-tenant authentication: each client company or distributor sees only their own data. Granular roles and permissions per account. SSO support for enterprise providers (Azure AD, Google Workspace).
- Real-time operational dashboard: business KPIs visible to the client without calling the sales rep — order status, invoices, service metrics.
- Request and approval flows: order, quote, technical support, or documentation requests with configurable review flows and automatic notifications.
- Exports and reports: PDF/Excel report generation that clients can export on demand — period orders, invoices, service summaries.
Architecture and stack: what technologies work in production
- Frontend: Next.js with TypeScript for performance and SEO (if the app is public), or React SPA for authenticated internal apps. Tailwind CSS for development speed.
- Backend: Node.js/Express or Python/Django for REST APIs. PostgreSQL for relational data with high integrity. Redis for sessions and cache.
- Authentication: NextAuth.js or Auth0 for apps with multiple SSO providers. Always HTTPS, rotating refresh tokens, and secure session management.
- Infrastructure: Vercel or Railway for Next.js frontends, Railway/Render/AWS for backends. RDS PostgreSQL for production. S3/Cloudflare R2 for document storage.
Real costs and timelines for a B2B web application
- Basic client portal (authentication + dashboard + order/invoice queries): €8,000-€20,000. Timeline: 6-10 weeks.
- Distributor platform with order management, stock, and content: €20,000-€50,000. Timeline: 12-20 weeks.
- Complex B2B app with multiple roles, approval flows, and bidirectional ERP integrations: €40,000-€100,000. Timeline: 20-40 weeks.
- Annual maintenance: 15-25% of development cost. Includes dependency updates, monitoring, bug fixes, and technical support.
Want to digitalise your client or distributor relationships with a custom web application?