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Integration · Commerce
Shopify ERP integration for brands that ship real volume
Shopify is an excellent storefront. It is not an inventory, purchasing or accounting system for a multi-channel business. The integration's job is to let Shopify sell while the ERP runs operations — without anyone exporting CSVs.
Overview
What this integration is for
We build Shopify integrations on the Admin API and webhooks, with clear rules about which system owns each piece of data and what happens when either side is unavailable.
01Data
What data syncs, and in which direction
| Entity | Direction | Notes |
|---|---|---|
| Orders | App → ERP | New and paid orders imported as sales orders with lines, discounts, shipping, taxes and payment status. |
| Customers | App → ERP | Matched by email with rules for guest checkouts; B2B companies mapped to ERP accounts. |
| Products & variants | ERP → App | ERP as master for SKUs, prices and core attributes; merchandising content can stay in Shopify. |
| Inventory levels | ERP → App | Available quantity per location pushed with optional safety buffers. |
| Fulfilments & tracking | ERP → App | Shipments and tracking numbers posted back so customers are notified. |
| Refunds & returns | App → ERP | Refunds create credit notes; returns create return receipts. |
| Payouts | App → ERP | Shopify Payments payouts reconciled against orders, fees and refunds. |
02Use cases
Common use cases
01
Single inventory across channels
One stock figure feeding Shopify, wholesale and marketplaces.
02
Automated fulfilment
Orders flow to warehouse picking and tracking returns to Shopify automatically.
03
Accurate accounting
Sales, taxes, fees and payouts posted correctly without manual journals.
04
B2B and DTC together
Shopify for consumers, ERP portal or Shopify B2B for trade, with one ledger.
03 — Architecture
API architecture
Shopify pushes order and refund events through webhooks to a receiving endpoint that verifies the HMAC signature, stores the payload and acknowledges quickly. Processing happens asynchronously from a queue, so a slow ERP never causes Shopify to time out and retry.
Outbound updates — stock, prices, fulfilments — are batched and sent through the Admin API, respecting Shopify's rate limits. A scheduled reconciliation job compares recent orders on both sides to catch anything a webhook missed.
04Reliability
Authentication, errors and retries
01
Authentication
A custom or private app installed on the store with scoped Admin API access tokens limited to the resources the integration needs. Tokens are stored in a secrets manager, never in code.
02
Error handling
Each order is processed with its Shopify ID as an idempotency key. Validation errors (unknown SKU, tax mismatch) go to an exception queue with the reason, visible to the operations team.
03
Retry strategy
Transient failures and rate-limit responses retry with exponential backoff. After the final attempt, messages move to a dead-letter queue and an alert is sent; they can be replayed once fixed.
05 — Data mapping
Field mapping essentials
| Shopify | ERP |
|---|---|
| order.id / name | Sales order referenceBoth stored for traceability |
| line_items.sku | Product (internal reference)Unknown SKUs go to exceptions |
| customer.email | PartnerMatched, not duplicated |
| tax_lines | Tax / fiscal positionMapped per jurisdiction |
| shipping_lines | Delivery method & charge |
| inventory_level.available | Free quantity per locationLess safety buffer |
06 — Automation
Automation opportunities
- Auto-confirm paid orders and release them to picking by carrier cut-off
- Hold high-risk or address-mismatch orders for review
- Create purchase proposals when online demand pushes stock below reorder points
- Send low-stock alerts per channel before products sell out
07 — Security
Security considerations
Webhook payloads are verified with Shopify's HMAC signature before processing. Access tokens have minimum scopes and are rotated when staff with access leave. Customer personal data is only stored where operationally necessary.
Related
Where this integration fits
Specialised pages
Other integrations
Often connected together
WooCommerceWooCommerce orders, products, stock and customers connected to your ERP via REST and webhooks.AmazonAmazon Seller Central and FBA orders, inventory, fees and settlements connected via SP-API.StripeStripe payments, subscriptions, refunds, fees and payouts reconciled in your ERP.PayPalPayPal payments, refunds, fees and settlements reconciled with ERP orders and invoices.
Insights
Related reading
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FAQ
Frequently asked questions
Should we use an existing Shopify connector?
Evaluate it first against your rules for customers, taxes, variants, bundles and multi-location stock. If it fits, it is usually the cheapest option. If it needs heavy modification, a purpose-built integration is easier to own.
How quickly does stock update in Shopify?
Typically within a few minutes. We batch updates and apply buffers rather than pushing every single stock movement.
Can we handle bundles?
Yes. Bundles sold in Shopify can explode into component lines in the ERP so stock is deducted correctly.
Next step
Connecting Shopify to your ERP?
Tell us your volumes, channels and data rules. We will outline the architecture and the risks before anything is built.