Custom Fields & Metafields

Why Custom Fields & Metafields needs Custom Migration

Business-critical values often live in Magento EAV attributes, Shopify metafields, WooCommerce custom fields, or order extras—not in the default entity set. When themes, apps, or integrations depend on those fields, Custom Migration for custom fields & metafields builds explicit export/import mapping.

Who this customization is for

• Stores whose theme or apps read product/customer/order metafields
• Merchants with Magento EAV attributes that must become Shopify metafields or Woo meta
• Teams connecting ERP or subscription tools that require specific keys
• Catalogs where only a subset of custom fields should move

Common use cases

• Product metafields that drive theme blocks, filters, or subscription apps
• Customer metafields for wholesale tiers, tax IDs, or CRM IDs
• Order custom attributes required by fulfillment or ERP connectors
• Namespace and key naming that must match target metafield definitions
• Selective migration of only the fields the new storefront needs

What Cart2Cart customizes

Migration Experts inventory source fields, map them to target namespaces/keys, and verify sample records in admin and (where relevant) storefront. Unused fields can be skipped to keep the destination clean.

Platform considerations

Shopify metafield definitions, WooCommerce post meta, and Magento attributes each have typing and namespace rules. Custom Migration aligns types and keys so apps keep working after cutover.

Note: The Target platform may require installing additional apps, plugins, or add-ons when a capability is not available by default. Custom Migration can map and import the data, but those Target-side apps/plugins often need to be installed and configured so the feature works in admin and on the storefront.

The best way to make sure everything is mapped correctly is to run a Demo Migration with your real Source platform data, then carefully check how entities look on the Target store before Full Migration.

Checklist for evaluating this customized migration

• Export attribute/metafield keys for products, customers, and orders you must keep.
• Map each source field to a target namespace/key or native field.
• Flag fields required by themes, apps, or ERP connectors.
• Skip unused legacy fields to keep the destination clean.
• Verify sample records in admin (and storefront if theme-driven) after Demo.

How to apply for this customization

1. Schedule a Call and list the custom fields or metafields you must keep.
2. Provide source/target carts and whether fields belong to products, customers, or orders.
3. Share examples of attribute codes / metafield keys.
4. We design the mapping, test on Demo data, then apply it in Full Migration.

Self-service Additional Options vs Custom Migration

The Wizard can skip custom attributes, but it does not design metafield namespaces. Custom Migration is the path when themes/apps depend on specific keys.

• Skip migration of custom attributes — Self-service: Omit custom attributes in a self-service run when you do not need them on Target. Choose Custom Migration when: Custom Migration when you must keep and remap EAV attributes, metafields, or order/customer extras to Target namespaces.

Availability depends on your Source → Target pair—confirm checkboxes in the Migration Wizard Entities / Additional Options step. See the Additional Options guide and Additional Options FAQ for pair-specific details. If Wizard options are not enough, schedule a Custom Migration call.

Already ran a self-service migration?

Yes—you can still apply this Custom Migration after a Wizard (self-service) run. Cart2Cart can restart migration with the customized rules; the Target store typically needs Clear current data on Target Store before Migration (or an equivalent cleanup of the entities from the previous self-service migration) so customized results are not mixed with the old import. Share your Source/Target carts and what already moved—Migration Experts will confirm the safest clear-and-rerun plan before Full Migration. Schedule a call if you already completed a Demo or Full Wizard migration and need customization next.

Case studies from real Custom Migrations

Cart2Cart Migration Experts have delivered custom work related to Custom Fields & Metafields across 117 recorded customization projects spanning 32 Source→Target platform pairs. Below are pairs we see most often, the entities typically involved, and sample data volumes when available.

Platform pairs already in focus

• WooCommerce → Shopify — 29 customization projects
• Magento → Shopify — 23 customization projects
• Magento → WooCommerce — 8 customization projects
• BigCommerce → Shopify — 7 customization projects
• PrestaShop → Shopify — 6 customization projects
• Magento → Magento — 3 customization projects

Entities commonly customized

• Products — seen in 75 related projects
• Customers — seen in 57 related projects
• Orders — seen in 56 related projects
• Categories — seen in 32 related projects
• Coupons — seen in 10 related projects

How much data was migrated

Among projects with recorded store size, median migration volume is about 14.6K records, with larger builds reaching roughly 222.7K at the 90th percentile and peaks near 2.6M. Exact counts depend on products, customers, orders, and related entities in scope.

Sample projects

• BigCommerce → Shopify — entities: Coupons 2.2M, Orders 302.3K, Customers 141.3K, Products 8.5K — total volume ~2.6M
• Magento → Shopify — ~371.3K records migrated
• Magento → WooCommerce — entities: Orders 175.5K, Customers 62.1K, Products 1.4K, Reviews 336 — total volume ~239.4K
• Magento → Magento — ~171.9K records migrated

Every store is different—share your Source/Target carts and entity scope on a Migration Expert call and we will estimate a similar Custom Migration path.

What we need to scope custom fields & metafields

Metafield namespaces, EAV attributes, and plugin-added properties are unique to each merchant’s catalog and apps. We cannot assume which keys matter for ERP, SEO, or storefront themes until we see your Source definitions and sample values.

Provide staging or production access (admin/API) so Experts can inventory attributes and destination metafield targets. If access is restricted, send a database dump (and metafield/attribute exports if available); dump analysis typically requires a deposit to cover environment setup and field-by-field review.

Tip: Initial data-structure analysis is much more efficient when you prepare exact examples of the important attributes and fields on the Source, plus how each should be mapped on the Target store (sample products/customers/orders with field names, values, and desired Target destinations). Clear examples reduce discovery time and help Migration Experts quote and implement the customization accurately.

FAQs

Can every EAV attribute become a Shopify metafield?

Most transferable values can, subject to type limits. We confirm definitions before Full Migration.

Do you migrate empty or obsolete fields?

We recommend skipping noise. You choose the allowlist.

Will apps auto-detect migrated metafields?

If namespaces/keys match what the app expects, usually yes. We align naming with your app docs.

Don’t leave metafields behind—talk to Cart2Cart.