BigCommerce SAP Business One integration, priced from the ERP.

ProjectThunder integrates BigCommerce with SAP Business One for B2B companies. ProjectThunder is a California B2B ecommerce studio, founded in 2004 and a BigCommerce Partner, that builds Stencil and Catalyst storefronts, sets up B2B Edition and integrates BigCommerce with SAP, Microsoft Dynamics and Sage. On Business One it connects price lists, special prices, stock by warehouse, sales orders, invoices and credit, through the Service Layer or the DI API, while your Business One partner runs the ERP.

The studio has launched 150 B2B storefronts across ERPs, its median client relationship is 10 years, and everyone works California hours, developers included.

The name says SAP, and a lot of BigCommerce SAP advice assumes ECC or S/4HANA. Business One is a separate product for small and midsize companies, with its own data model and its own ways in. Most of what applies to the larger SAP systems does not carry over:

• No IDocs, BAPIs or condition technique. Business One is reached through the Service Layer or the DI API, and its pricing is a set of price lists and special prices rather than a configured pricing procedure.
• Customers are business partners. Each has a code, bill-to and ship-to addresses and contact persons, and the store account has to map to the right one.
• Two database versions. Business One runs on Microsoft SQL Server or SAP HANA, on premises or hosted by a partner, and the version decides which API you can use.
• Your customizations count. User-defined fields and add-ons are common, and the integration has to fill the ones your business requires on a sales order.

ProjectThunder also integrates BigCommerce with SAP ECC, S/4HANA and ByDesign, and with any other SAP system that has an API. If you are on one of those, the page you want is BigCommerce SAP integration.

BigCommerce is the straightforward end: documented REST and GraphQL APIs, webhooks, price lists and customer groups, with B2B Edition adding company accounts and buyer roles. On the Business One side there are three routes:

• Service Layer. SAP’s web API for Business One, an OData interface over HTTPS. Recent 10.0 releases run it on both the HANA and SQL Server versions, and SAP now treats OData v4 as its main protocol. For a new build this is the default, because any modern integration can call it.
• DI API. The older COM interface. It runs on a Windows machine next to the Business One database, so it suits older SQL Server installs without a Service Layer and integrations that already live in an add-on. If Business One sits in your office, a small Windows service on site can use it and connect out to the store side.
• A connector app. Packaged apps in the BigCommerce App Marketplace map standard Business One objects to BigCommerce. They are the fastest route when your pricing and stock fit their model. The section on connectors below covers what their listings say.

Whichever route you take, writes go through the Service Layer or the DI API. SAP does not support writing to the Business One database directly, so reading it with SQL for reports is common and writing to it is not an option.

Every B2B storefront asks its ERP the same questions. On Business One they come down to these six, and getting them right is most of the project.

1. Price lists. Each business partner is assigned a price list, often derived from a base list by a factor. A price list maps cleanly to a BigCommerce price list and customer group, so this part can be synced.
2. Special prices. Special prices for business partners, period and volume discounts and discount groups sit on top of the price list, with date ranges and quantity breaks. This is where copied prices drift. Ask Business One for the price it would charge that business partner for that item, quantity and date, and cache the answer.
3. Stock by warehouse. Business One tracks in stock, committed and ordered per warehouse, and available is in stock minus committed plus ordered. Decide which warehouses serve the store and which figure it shows. Total stock across every warehouse is rarely the right answer.
4. Order write-back. The web order becomes a Business One sales order for the right business partner and ship-to address, with tax and freight handled, and the store keeps the Business One document number. An idempotency key on submission stops a retry from creating two orders.
5. Invoices. A/R invoices and open balances, shown in the buyer’s account so they can find and pay what they owe without calling.
6. Credit. The business partner’s credit limit and account balance, and a decision about what the store does when an order would go over the limit: block it, warn the buyer or send it to approval in Business One.

Numbers five and six are the ones most often left out of scope, and they are what turns a catalog into an account portal buyers actually log in to.

The BigCommerce App Marketplace lists SAP Business One connectors. What their own listings describe:

• Bizweaver, from Third Wave Business Systems. Pre-built, bi-directional workflows for products and SKUs, inventory, orders, customers, bill-to and ship-to information, and shipping status and tracking.
• APPSeCONNECT. Customers and web orders into the ERP; items, price changes and stock levels from the ERP to BigCommerce, with a choice of three stock calculations. The same app also lists other ERPs.

Both listings note that the app may not be fully compatible with multi-storefront. iPaaS platforms and build-to-order connectors are also on offer. These summaries come from the vendors’ listings as of November 2026, so confirm current coverage with the vendor.

Neither listing describes special prices per business partner, credit position or B2B Edition company accounts. If those matter to your buyers, ask the vendor directly, or plan a hybrid: a connector for catalog, stock and orders, and a small custom layer for pricing and the account portal. A fully custom build makes sense when pricing, approvals or user-defined fields are central to how you sell.

• Special prices were copied. The price list synced fine, the special prices and quantity breaks were flattened, and the customers with negotiated prices are the ones who notice.
• The wrong stock figure. In stock synced instead of available, or every warehouse added together, so the store promises what it cannot ship.
• Orders duplicate. No idempotency key, so a retry or a double click creates two sales orders.
• Units of measure disagree. The item is sold by the case in the store and priced by the each in Business One, and order lines arrive with the wrong quantity.
• Required fields are missing. A user-defined field the business made mandatory is not filled, and order write-back fails for every order until somebody notices.
• The integration stops quietly. A Service Layer session expires and the integration never logs back in, or the DI API service runs on a machine nobody owns.
• An upgrade changes the ground. A Business One upgrade or feature pack changes behavior the integration relied on, such as the move from OData v3 to v4. Test the integration in a test company before each upgrade.

Each of these is cheaper to design out than to find in production, and each is easier to diagnose when the integration logs what Business One returned.

Every ProjectThunder project starts with 50 to 100 hours of planning at $100 an hour: your Business One version, which API each flow uses, how pricing is set up and what the six contracts look like. The build then runs at $185 an hour, or $165 an hour prepaid on 7-day terms, with four layers of testing before launch, and a 20 to 50 hour monthly retainer after it. We integrate Business One; your Business One partner implements, supports or moves the ERP. The detail is on our process page.