Past a certain size, Shopify is rarely the only system in the business. Stock, purchasing, warehouse picking, marketplaces and accounting run somewhere else, and the integration decides whether stock levels are right, orders reach the warehouse and finance can close the month without spreadsheets. Connectors exist for the common systems. None of them makes the decisions for you.
Start with data ownership
Every field needs exactly one system of record. When a price is maintained in two places, the wrong one eventually wins. A typical split that works:
| Data | Usually owned by | Direction |
|---|---|---|
| SKU, barcode, cost price | ERP / inventory system | ERP → Shopify |
| Product copy, images, SEO fields | Shopify | stays in Shopify, never overwritten |
| Selling price | ERP or Shopify — pick one | one direction only |
| Stock levels | ERP / inventory system | ERP → Shopify, near real time |
| Orders and customers | Shopify | Shopify → ERP |
| Fulfilment status and tracking | ERP / warehouse | ERP → Shopify, triggers the shipping email |
| Invoices and payouts | Accounting system | via the ERP or a tool such as A2X |
The most common conflict is product content. Many connectors can push descriptions from the ERP; if your marketing team edits copy and SEO fields in Shopify, the next sync erases their work. Restrict what the connector is allowed to write.
The common options
- Linnworks: popular with UK multichannel sellers; manages stock and orders across Shopify, Amazon and eBay with a direct Shopify integration.
- Brightpearl: retail operations and inventory for growing brands, with a Shopify integration covering products, stock, orders and fulfilment.
- NetSuite: usually connected through Oracle's NetSuite Connector or an integration platform such as Celigo; flexible, but needs careful field mapping.
- Accounting only: Xero and QuickBooks connect through their own apps or settlement tools such as A2X, which reconcile Shopify payouts with fees and refunds.
- Custom integration via the Shopify Admin API: worth it for an in-house ERP, unusual processes or when a connector misses a core function.
Before choosing, read a connector's recent reviews and changelog. For an integration every order passes through, responsive support matters more than the feature list.
Where integrations break
Variants and options
Shopify allows three options and up to 2,048 variants per product. ERPs often model parent and child items with any number of attributes. A product with four attributes either fails to sync or creates duplicates. Map the structure first, and make sure every SKU is unique.
Bundles and kits
A three-item bundle is one product in Shopify and three stock lines in the warehouse. Whether the connector explodes bills of materials or treats the bundle as its own SKU decides whether stock stays accurate.
Partial shipments, cancellations and refunds
Test more than the happy path: a backordered line shipped later, a cancelled item, a return received at the warehouse, a refund issued in Shopify. Each movement has to land on both sides or stock, invoices and refunds drift apart.
Multi-currency and tax
If you sell to the EU or the US from the UK, orders arrive in several currencies and with different tax treatment. Decide whether the ERP records the presentment currency or your base currency, and check that VAT and duties map to the right ledger codes. Our guide to selling to the US after de minimis ended covers the duty side.
Sync frequency
A stock sync every 30 minutes oversells during a promotion when you also sell on marketplaces. Ask how often stock syncs and whether orders reserve stock immediately.
How we run an integration
- Agree data ownership field by field and write it down.
- Choose a connector — or decide a custom integration is needed.
- Clean the catalogue: unique SKUs, variants within three options, barcodes populated.
- Run test orders for the standard, partial, cancelled, refunded and international cases.
- Launch and watch the first days closely: stock variances, missing orders, error logs.
Planning a replatform at the same time? Build the integration into the migration plan — see what breaks in a Shopify migration. Where no connector fits, we build the integration as a custom Shopify app.