When a buyer in an industrial setting orders a line item, they are usually planning more than a goods receipt -- a production batch, an assembly date, a construction site. That is why they do not need vague wording like "in stock" or "available soon," but a reliable statement: how many units are free to sell at which warehouse, and on which day they will arrive? Market research confirms this expectation. Showing product availability online is one of the five core capabilities B2B customers expect from every supplier (McKinsey B2B Pulse). When it is wrong, the consequences in industry are immediate: unplanned production downtime costs industrial manufacturers around 50 billion US dollars per year (Deloitte). This article shows how an available-to-promise logic via the ERP interface displays warehouse, quantity, replenishment time and a realistic delivery date live in Shopware.
Why Buyers Expect Reliable Availability
B2B purchasing has shifted from assisted selling to digital self-service. 67 percent of B2B buyers now prefer a rep-free buying process in which they order without consulting the sales team (Gartner, 2026). But this independence only works if the store provides the information sales used to confirm over the phone -- above all reliable stock and dates. When those are missing, self-service breaks down, the buyer picks up the phone or checks the competition.
Reliable availability does not stand alone. B2B customers who expect one of the core omnichannel capabilities are 80 to 90 percent likely to want all the others (McKinsey B2B Pulse) -- from real-time information and a continuous order history to a dependable delivery commitment. Presenting availability cleanly therefore contributes to the whole set of expectations that drives supplier choice. Availability data can also feed automated back-in-stock notifications; how such flows are built is described in the article on B2B marketing automation and email flows.
Production Planning
Anyone scheduling manufacturing, assembly or construction needs a firm date -- not a range of "3 to 5 days".
Their Own Delivery SLAs
Many buyers have committed delivery dates to their own customers and pass that pressure on to the supplier.
Inventory Planning
Reliable inbound dates allow lean stockholding without building safety stock blindly.
Planning Certainty
A calculated delivery date replaces the email inquiry and makes the ordering process predictable.
Relief for Sales
Every availability question answered in the store is one fewer call for the inside sales team.
Supplier Loyalty
Those who inform reliably get reordered. Vague or wrong information is a common reason to switch suppliers.
Vague Information Stops Production Lines
In discrete manufacturing and the process industry, a misstated stock figure is not a cosmetic flaw but an operational risk. If an ordered part for which the store signaled availability is missing, in the worst case the line stops. While the largest share of unplanned downtime, around 42 percent, is due to equipment failure (Deloitte), missing raw materials and spare parts are among the avoidable causes that a correct availability display addresses directly. In the digital spare parts business in particular, stock accuracy decides whether a repair is possible today or only next week.
That material availability is a structural issue is clear from the executive perspective: 72 percent of industrial decision-makers rate the shortage of critical materials and supply chain disruptions as the biggest uncertainty for their industry (Deloitte). For the B2B store this yields a clear task. It should display honestly rather than optimistically -- better a later but dependable date than an early commitment that fails. A conservatively calculated availability protects both sides: the buyer from downtime, the supplier from complaints and returns.
Optimistic Stock Is Expensive
Available-to-Promise: From a Stock Figure to a Dependable Date
Available-to-promise (ATP) describes the quantity of an item that can actually be committed at a given point in time. ATP is not identical to physical stock but a calculated figure: reserved quantities from open orders are subtracted from stock, planned inbound from supplier orders is added, and the time at which that inbound arrives is taken into account. Only this calculation delivers the number a buyer really needs -- and the date on which a quantity beyond free stock becomes deliverable.
- Physical stock per warehouse -- the actual quantity on hand in the inventory system.
- Reserved quantities -- already allocated by open orders, picking or framework agreements.
- Planned inbound -- confirmed supplier orders with an expected goods receipt date.
- Replenishment time -- how long resupply takes once stock is depleted.
- Warehouse and route -- which site ships and the transit time that results.
The Basic ATP Formula
The difference from a classic status light is economically relevant. Nearly 80 percent of B2B customers say a reliable performance commitment is critical to their brand loyalty (McKinsey B2B Pulse). An ATP-based date commitment is the digital equivalent of this expectation: it replaces the non-binding "usually available soon" with a concrete, data-derived statement the buyer can rely on.
What the Store Should Actually Display
The step from vague to reliable can be pinned to specific fields. What matters is that every value comes from a dependable data source and carries a data timestamp -- the buyer should recognize that they are seeing a current figure, not one imported overnight.
| Field | Vague (standard) | Reliable (ATP) |
|---|---|---|
| Availability | "in stock" / "out of stock" | 1,240 units free to sell |
| Warehouse | not shown | Nuremberg, inbound from Hamburg |
| Quantity above stock | green despite low stock | partial now, rest on date |
| Delivery date | "3 to 5 days" | Thu, 22 May (calculated) |
| Replenishment | unknown | 5 business days from supplier |
| Data timestamp | overnight import | sync in under 60 seconds |
The quality of this display is a noticeable differentiator in a large market: B2B online trade via stores and marketplaces in Germany recently grew by 7 percent to 509 billion euros (IFH Cologne). Working with dependable dates sets you apart from suppliers who only show a stock light. Technically, the lever for this is the connection to the leading data source -- the inventory system via an ERP interface.
The ERP Interface as the Data Source
Stock, reservations and inbound dates live in the ERP or inventory system, not in the store. A dependable availability display therefore requires a clean interface architecture that carries this data in real time into the Shopware storefront. A combination has proven effective: periodic delta sync for the breadth of the catalog and event-based push for time-critical items whose stock should update in the store on every posting. The fundamentals of this connection are covered in the guide to ERP integration in B2B.
Delta Sync
Instead of reconciling the whole catalog, only changed stock is transferred. This keeps the load on the ERP low and the display current.
Event Push
On every goods movement the ERP sends an event to the middleware. Time-critical items stay current with almost no delay.
Reservation Logic
Open orders and picking reduce the free quantity. Without this offset, overselling occurs.
For a typical B2B catalog of 30,000 to 50,000 items, a delta sync reduces the transfer volume by over 90 percent compared with a full reconciliation (project experience). The middleware does more than transport: it calculates the ATP quantity, manages the reservations and ensures the store shows a sensible last-known value rather than an error even during a brief ERP downtime. An event-based push typically updates time-critical items in under 60 seconds (project experience).
Do Not Forget Reservations
Calculating Delivery Time Realistically
A dependable delivery date is more than stock plus a flat rate. It is made up of several building blocks calculated one after another in the ATP run. For quantities exceeding free stock, the inbound date is used; for immediately deliverable partial quantities, your own picking and shipping time applies.
- Determine the free quantity per warehouse from the ATP run.
- Split partial quantities: show the immediately deliverable share and the remainder on the inbound date separately.
- Add picking and shipping time of the shipping warehouse, including the cutoff for same-day dispatch.
- Account for transit time of the route or shipping carrier.
- Correctly skip working days, holidays and weekends in the target date.
For the buyer, the separate display of partial quantities is particularly valuable: they see that, for example, 340 units ship immediately and the remaining 660 on the confirmed inbound date. In many manufacturing scenarios the immediate partial quantity is enough to keep working, while the remainder follows on a scheduled date -- information that a simple "out of stock" hides entirely.
Implementation in Shopware: Process and Timeline
In Shopware the ATP display is mapped through a dedicated data field per product and warehouse that the middleware maintains. The storefront renders the availability widget with quantity, warehouse and calculated date from it. Thoughtful caching is important: the display should be current without hitting the ERP on every page view -- a short-lived cache with event invalidation resolves this trade-off. If a migration to Shopware without ranking loss is on the agenda anyway, the ATP connection can be built directly into the new concept. The initial implementation is realistically achievable in 6 to 10 weeks in the mid-market (project experience).
- Clarify data sources: define the leading system for stock, reservations and inbound.
- Define ATP rules: align formula, buffers, partial-quantity logic and rounding with sales and planning.
- Build middleware and sync: set up delta sync plus event push, implement reservation offsetting.
- Develop the storefront display: implement the availability widget, date presentation and caching in Shopware development.
- Test and go live: reconcile against the ERP with real stock data, then go live with accompanying consulting.
Effort and Payback
Challenges in Practice
Real-time availability is a data-quality project as much as an integration one. The biggest obstacles rarely lie in the display itself but in the underlying processes. Ongoing interface monitoring is therefore part of the solution, so that silent sync errors do not lead to wrong commitments.
- Data quality in the ERP: missing stock and unmaintained inbound dates feed straight into the display.
- Reservation logic: open orders and picking must be offset cleanly.
- Cache versus real time: balance performance and currency through event invalidation.
- Multiple warehouses: merge site-specific stock and routes correctly.
- Supplier data: in drop-ship scenarios the date depends on the supplier's data quality.
A store that honestly shows when something will arrive earns more trust than one that always reports "available" and then disappoints.
Sources and Studies