How to Integrate an ERP with Shopify: Connectors, Middleware, or Custom API

If someone on your team spends their mornings copying Shopify orders into your ERP, updating stock counts by hand, or fixing wholesale prices that don't match, you already know why ERP integration matters.

The harder question is how to do it. There are three main routes: a ready-made connector, a middleware platform, or a custom integration built on Shopify's APIs. Each can work well, and each can fail badly when it's the wrong fit.

This guide explains the three options in plain language, what to plan before you choose, and the mistakes that cause most integration headaches.

The Short Answer

To integrate an ERP with Shopify, you can use a ready-made connector app, a middleware (iPaaS) platform, or a custom API integration. Start with a connector if one exists for your ERP and covers your needs. Use middleware when several systems need to stay in sync. Build custom only when your ERP or your business rules are too specific for the other two. Whichever you choose, the planning matters more than the tool.

What an ERP Integration Actually Does

An ERP integration moves data between Shopify and your ERP automatically, so nobody has to retype it. Shopify's own guide to ERP integration describes the goal simply: when one system is updated, the other is notified and updated too.

Here's the data that typically flows each way:

How It Works Under the Hood

Shopify integrations rely on two mechanisms:

• The Admin API handles requests from your systems, such as reading orders or updating inventory.

• Webhooks work the other way: Shopify sends a notification the moment something happens, such as a new order being created or a stock level changing.

Whichever route you choose, a connector, middleware, or custom code, it's built on these same mechanisms. The difference is who builds and maintains the logic in between.

Option 1: Ready-Made Connectors

A connector is an app built specifically to link Shopify with one ERP. You install it, sign in to both systems, choose what syncs, and map the fields.

Shopify runs a Global ERP Program with certified connector apps for major ERPs. According to Shopify, its partners include Microsoft Dynamics 365 Business Central, Oracle NetSuite, Infor, Acumatica, and Brightpearl by Sage, and certified apps go through a review covering security and performance before they're listed.

Best for:

• Stores using a popular ERP that has a solid Shopify connector

• Standard flows: orders in, stock and prices out

• Teams without in-house developers

Strengths:

• Fastest to set up

• The vendor maintains it as Shopify and the ERP change

• Lower upfront cost than a custom build

Limits:

• You work within the connector's settings. If your business rules don't fit, there may be no workaround.

• Not every connector supports every Shopify feature. If you sell B2B, check specifically that it supports Shopify's companies, catalogs, and payment terms.

• Connecting more systems usually means more connectors, each configured separately.

Option 2: Middleware (Integration Platforms)

Middleware sits in the middle, translating and routing data between Shopify, your ERP, and other systems. The most common type is an iPaaS (integration platform as a service): a cloud tool with pre-built connectors for many apps and a visual way to design data flows.

Instead of linking each system to every other system, everything connects to the middleware. That makes it easier to manage when you have several systems, such as an ERP, a warehouse system, a CRM, and a marketplace.

Best for:

• Businesses connecting three or more systems

• Data that needs reshaping between systems (different product codes, units, or tax rules)

• Teams that want to adjust flows without rewriting code every time

Strengths:

• One central place to see and manage every integration

• More flexible than a single connector

• Usually less custom code than building everything from scratch

Limits:

• Ongoing subscription costs, often tied to the number of connections or the volume of data

• Someone still needs to design, map, and maintain the flows properly

• Another system to monitor, and another place where something can go wrong

Shopify's guide describes iPaaS as well suited to keeping several systems such as an ERP, CRM, and warehouse system in sync.

Option 3: Custom API Integration

A custom integration is code written specifically for your business. It uses Shopify's Admin API and webhooks on one side and your ERP's API (or file exports) on the other, with your own rules in between. It's usually packaged as a custom app.

Best for:

• ERPs with no reliable Shopify connector, including older or industry-specific systems

• Business rules no connector or middleware handles well, such as complex B2B pricing, kits and bundles, or unusual fulfillment logic

• Businesses that need full control over how and when data moves

Strengths:

• Built exactly around your process

• No per-connection subscription fees

• You own the code and the logic

Limits:

• The highest upfront cost and the longest build time

• You're responsible for maintenance. Shopify releases new API versions regularly, and custom code needs updating to keep up.

• It needs proper error handling, logging, and monitoring built in from the start

Shopify's own guidance is direct on this point: custom integrations bring more risk and maintenance, so they're best kept for systems with no good alternative. We agree. A custom build should be a deliberate choice, not the default.

Side-by-Side Comparison

It's common to combine them. For example, a certified connector handles orders and inventory, while a small custom app handles one B2B pricing rule the connector can't.

The Planning Decisions That Matter Most

Most integration problems aren't caused by the tool. They're caused by decisions nobody made before the build started. Settle these first.

1. Which System Is the Source of Truth?

For every type of data, decide which system "wins" when the two disagree.

Write this down. Shopify's own guidance recommends naming the system of record for every field that moves between systems.

2. How Often Does Each Type of Data Sync?

Not everything needs to be instant. Orders and stock usually need to move quickly, because overselling or slow fulfillment affects customers directly. Product descriptions or reporting data can often sync on a schedule.

3. How Do Fields Map Between Systems?

Two systems rarely describe things the same way. Product codes, units of measure, tax codes, and variant structures all need clear mapping rules. This is usually the most time-consuming part of any integration, whichever route you choose.

4. What Happens When Something Fails?

Something will fail eventually: a network timeout, a product code that doesn't exist, an ERP that's down for maintenance. Decide in advance:

• Does the integration retry automatically?

• Who gets alerted, and how?

• Where can someone see failed records and fix them?

5. Who Owns the Integration?

Name a person responsible for each integration, someone who notices when it breaks and knows who to call. Integrations without an owner tend to fail quietly.

B2B and Wholesale Considerations

Wholesale is where ERP integrations get most demanding, because so much B2B logic lives in the ERP: account-specific pricing, credit limits, payment terms, and customer-specific product lists.

Shopify's native B2B features (companies, catalogs, payment terms, and volume pricing) give integrations a clear place to put that data. Shopify's B2B features overview notes that you can connect ERP and accounting systems to your B2B store, and build your own integrations with B2B APIs.

A few things to check before you choose a route:

• Does the connector support Shopify B2B? Some integrations only handle retail orders. Confirm it can create and update companies, locations, and catalogs.

• Where does pricing live? If prices are managed in the ERP, plan how they'll reach Shopify catalogs and how often.

• What's your Shopify plan? Standard plans support up to three B2B catalogs, assigned through Shopify Markets. If your ERP holds pricing for many individual accounts, you may need Shopify Plus for customer-specific catalogs.

• How do payment terms and credit limits sync? Decide whether credit checks happen in Shopify, the ERP, or both.

Our guide to [Shopify B2B on non-Plus plans](BLOG #5 URL) explains the catalog limits in more detail.

Common Integration Mistakes

• Choosing the tool before mapping the process. Decide what needs to flow, and how, before picking a connector or platform.

• Syncing messy data. Duplicate SKUs, inconsistent product codes, and outdated customer records get copied everywhere. Clean data first.

• No plan for failures. An integration that fails silently can oversell stock or lose orders for days before anyone notices.

• Two systems both trying to own the same data. If stock levels can be edited in Shopify and the ERP, they'll drift apart.

• Testing only with perfect orders. Test partial refunds, split shipments, cancelled orders, discount codes, and B2B orders with payment terms.

• Forgetting about maintenance. APIs change. Budget time every year to review and update the integration.

A Simple Project Plan

1. Map your current process. Write down how orders, stock, prices, and customers move today, including the manual steps.

2. Define the data flows. For each type of data: direction, timing, and source of truth.

3. Clean your data. Fix SKUs, duplicates, and inconsistent records before connecting anything.

4. Choose the route. Connector, middleware, custom, or a combination, based on the decisions above.

5. Build and map fields. Set up the connector or platform, or build the custom app.

6. Test with real scenarios. Use a development store or test environment and run every order type you handle.

7. Run in parallel if you can. Compare integration results against your current process for a short period before switching over fully.

8. Go live and monitor. Watch error logs, sync timings, and stock accuracy closely for the first few weeks.

9. Document and assign ownership. Make sure someone knows how it works and what to do when it breaks.

Frequently Asked Questions

How do I integrate my ERP with Shopify?

You have three main options: a ready-made connector app for your ERP, a middleware (iPaaS) platform that connects several systems, or a custom integration built on Shopify's APIs. Start by mapping what data needs to flow and which system owns it, then choose the route that fits.

Which ERPs have official Shopify connectors?

Shopify's Global ERP Program lists certified apps for ERPs including Microsoft Dynamics 365 Business Central, Oracle NetSuite, Infor, Acumatica, and Brightpearl by Sage. Many other ERPs connect through third-party apps or middleware.

Do I need Shopify Plus to integrate an ERP?

No. ERP integrations work on standard Shopify plans too. Plus becomes relevant if you need features such as unlimited B2B catalogs or customer-specific pricing that your ERP data depends on.

What's the difference between middleware and a connector?

A connector links Shopify to one specific system. Middleware sits between several systems and manages data flows between all of them from one place.

Is a custom ERP integration worth it?

It's worth it when no connector or middleware handles your ERP or business rules properly. Shopify itself recommends reserving custom integrations for systems without a good alternative, because they need more ongoing maintenance.

What data should sync between Shopify and an ERP?

Usually orders, customers, payments, and refunds from Shopify to the ERP, and inventory, prices, product data, and fulfillment updates from the ERP to Shopify. B2B businesses often add payment terms and account-specific pricing.

Planning an ERP Integration?

CodeVibez is a Shopify Plus Preferred Partner that has supported more than 1,000 Shopify stores across D2C, B2B, wholesale, ERP integrations, and point of sale.

We'll help you map your data flows, choose between a connector, middleware, or custom build, and set it up so it keeps working as your business grows. If a certified connector does the job, we'll tell you.

Schedule a free call or contact our team.