MedusaJS B2B e-commerce guide 2026
MedusaJS v2 is an open-source B2B e-commerce platform with modular Node.js architecture - GMI Software from Gdansk delivers contract pricing, credit limits and ERP integrations in EUR 55,000 - 120,000 projects (typical B2B scope with data migration). After discovery (DDT) we share fixed price and a migration roadmap within 48h.
What Medusa v2 offers for B2B (and what it does not do alone)
Medusa v2 is a commerce layer, not an ERP replacement. The platform supports per-customer price lists, minimum order quantities (MOQ), customer groups, order approval workflows and extensions for marketplace split checkout. Unlike pure D2C SaaS you avoid GMV fees - cost is infrastructure, dev team and integrations.
Typical B2B needs two data layers: Medusa holds catalog, cart, checkout and commercial rules; ERP (SAP, Comarch, Microsoft Dynamics, custom WMS) stays the source of truth for invoices, stock and credit limits. GMI designs event-driven sync to avoid price drift across channels.
The B2B storefront is usually Next.js with company login, per-account price views, multi-line carts and order history. The same Medusa Admin API can power a React Native app for field sales.
Core B2B modules to plan in discovery
Contract pricing: price lists tied to customer groups or individual B2B accounts, often with validity dates and per-market currency. Credit limits: block checkout when balance is exceeded or require prepayment for new accounts.
Approval workflows: a manager approves orders above a threshold before they hit ERP. Reorder and quick order: last-SKU lists per customer shorten purchase cycles in wholesale and distribution.
Integrations: product sync from PIM, stock from warehouse, shipment confirmations from WMS, pro forma invoices from ERP. In discovery we map which events are real-time versus nightly batch - that drives cost and SLA.
Medusa B2B vs Magento monolith / SaaS
Choose Medusa v2 when: you have complex per-customer pricing, need headless (web + app + maybe POS), want code ownership and no GMV fees, and your team or partner knows JavaScript/TypeScript.
Stay on SaaS (Shopify Plus, BigCommerce B2B) when: the catalog is simple, ERP integrations are standard, and fastest year-one go-live matters more than owning the stack.
Migrate from Magento 2 B2B when: license and maintenance cost grows, storefront performance drops on large catalogs, and mobile/omnichannel need separate engines. GMI typically migrates catalog, B2B customers and order history in phase 2 after checkout MVP.
Budget, timeline and delivery model
GMI ranges for Medusa B2B with ERP and migration: EUR 55,000 - 120,000 fixed price after DDT (1-3 week discovery). MVP checkout + contract pricing: 3-5 months. Full programme with migration and multiple integrations: 5-9 months.
Reference team: Medusa tech lead, 2 backend devs, Next.js frontend, QA and client-side product owner. 2-week sprints with demos, internal code review, architecture docs in English.
Post go-live we recommend a maintenance retainer (Medusa updates, monitoring, peak-season B2B support). Broader headless commerce context lives on our headless e-commerce page.
Pre-kickoff checklist for Medusa B2B
1) Where is the source of truth for prices and stock? 2) Which B2B customer groups and credit rules? 3) Do orders need manager approval? 4) Which systems integrate (ERP, PIM, WMS, deferred payments)? 5) Migrate order history or active customers only? 6) Business deadline (season, legacy decommission)?
Without answers, B2B quoting is guessing. GMI DDT ends with a phased roadmap, fixed-price ranges and an integration risk list - not generic slides.
Next step: B2B discovery
If you have an ERP + Medusa architecture sketch and B2B commercial rules list, contact GMI - you will get initial scope and budget ranges within 48h. A full fixed-price offer requires a DDT workshop with business and IT.
MedusaJS development: https://gmi.software/services/medusajs-development
Sources and references
MedusaJS v2 B2B documentation: https://docs.medusajs.com
Medusa price lists and customer groups: https://docs.medusajs.com/resources/commerce-modules/pricing
GMI MedusaJS development: https://gmi.software/services/medusajs-development
GMI headless e-commerce: https://gmi.software/services/headless-ecommerce
Frequently asked questions
- Does Medusa replace ERP?
- No - Medusa is the commerce layer (catalog, cart, checkout, B2B rules). ERP stays finance/WMS; we sync prices, stock, orders and credit limits via API or events.
- How long does Medusa B2B delivery take?
- MVP with contract pricing and checkout: 3-5 months. Programme with ERP, data migration and multiple integrations: 5-9 months. Discovery before kickoff reduces schedule slip risk.
- Does Medusa B2B support marketplaces?
- Yes - Medusa v2 has modules for split checkout and multiple sellers. In B2B marketplaces we often combine wholesale rules per vendor with central invoicing and operator-side ERP integration.
- Fixed price or T&M for B2B?
- After DDT we recommend fixed price on agreed scope - predictable budget for the CTO on complex ERP integrations. T&M stays for discovery or when the client wants a flexible backlog without frozen scope.
Content updated: July 2, 2026