Quick Takeaways
  • Most BigCommerce to Shopify migrations lose organic rankings not because of URL changes, but because 301 redirects are set up wrong or too late.
  • BigCommerce's product option structure doesn't map cleanly to Shopify's variant model — this trips up almost every DIY migration.
  • Customer passwords can't be migrated. Ever. Plan your re-engagement email before launch day, not after.
  • Shopify's checkout is locked (unless you're on Shopify Plus), so custom BigCommerce checkout logic needs an alternative solution before you flip the switch.

The Migration Problem Nobody Warns You About

Here's an uncomfortable truth: most BigCommerce to Shopify migrations don't fail because of bad data. They fail because store owners treat it like a copy-paste job and discover three weeks post-launch that their organic traffic dropped 40% and their checkout conversion rate is half what it was on BigCommerce.

We've handled dozens of platform migrations at SPS, and BigCommerce is one of the trickiest sources — not because it's complicated, but because it's similar enough to Shopify that people get overconfident. The databases look comparable. The concepts feel familiar. Then you go live and realize your faceted navigation URLs are all 404s, your product metafields didn't transfer, and your custom tax logic doesn't exist in Shopify's native ruleset.

This post is about what actually matters in a BigCommerce to Shopify migration — the stuff that moves the needle or breaks your store if you get it wrong.

Why BigCommerce Data Doesn't Just Drop Into Shopify

The Product Variant Problem

BigCommerce supports up to 600 variants per product and allows option sets to be shared across multiple products. Shopify caps variants at 100 per product and ties options directly to the individual product. That architectural difference creates real headaches during migration.

If you sell apparel or anything with size/color/material combinations, you may have products that simply can't exist in Shopify the way they do in BigCommerce without restructuring. One store we migrated had 12 products on BigCommerce that each had 200+ variants. We had to split several into separate product listings with a metafield-based relationship and a custom theme section to make them behave like a single product on the frontend. It took an extra week and a half. Nobody planned for it.

Check your variant counts before anything else. Export your BigCommerce catalog, run a quick filter in Excel or Google Sheets, and flag every product over 100 variants. Those need a plan before migration day.

Customer Data: What Moves and What Doesn't

Your customer names, addresses, order history, and email addresses migrate fine. Passwords do not — this is a Shopify platform limitation, not a migration tool issue. Shopify uses bcrypt hashing and has no mechanism to import third-party password hashes.

That means every single customer will need to reset their password after launch. If you don't have a solid email marketing sequence ready to handle that gracefully, you'll lose a chunk of returning customers who just assume something's broken and never bother logging in again. Send the reset prompt proactively. Make it feel like an upgrade, not a problem.

The SEO Migration Piece Most People Get Wrong

Losing SEO rankings during a platform migration is usually avoidable. But "usually" is doing a lot of work in that sentence. There are three places where BigCommerce-to-Shopify migrations bleed organic traffic, and most tutorials only mention one of them.

URL Structure Differences

BigCommerce URLs are configurable. Many stores have them set to /products/product-name/ or even just /product-name/. Shopify forces /products/product-name and /collections/collection-name. You can't override this structure (without some hacky redirect chains that create their own problems).

This means every product URL, collection URL, and blog post URL needs a 301 redirect mapped before you go live. Not after you notice the traffic drop. Before. We use a redirect mapping spreadsheet during pre-migration audit that maps every BigCommerce URL to its Shopify equivalent. It's tedious and worth every minute.

The Faceted Navigation SEO Trap

BigCommerce's faceted search often creates indexed URLs like /products/?brand=nike&color=red. If Google has indexed those URLs and you don't redirect them or handle them properly post-migration, you'll see 404s piling up in Search Console within days. Shopify handles filtered collections differently, and there's no automatic mapping between the two systems.

Our standard Shopify SEO setup post-migration includes auditing Search Console for any indexed faceted URLs from the old platform and building redirect rules to handle the most trafficked ones. For the long tail, a catch-all redirect to the relevant collection usually limits the damage.

A Real Example

One outdoor gear brand came to us after attempting a self-service migration from BigCommerce. Three weeks post-launch, organic traffic was down 34%. When we audited the situation, we found 1,847 broken URLs, zero 301 redirects set up (they assumed Shopify would handle it automatically), and their blog had been migrated without preserving the original slugs. Eight weeks of redirect work and content cleanup later, they were back to baseline. The migration itself would have cost them about $3,500 with a professional service. The recovery work cost significantly more.

Checkout and App Logic: The Hidden Rebuild Cost

If you've customized your BigCommerce checkout — custom upsells, loyalty point redemption at checkout, specialized shipping logic — you need to audit every single one of those features before migration. Shopify's standard checkout is locked. You can't modify the checkout template unless you're on Shopify Plus.

This is one of the most common post-migration surprises for stores doing $500K–$2M/year. They built smart checkout logic on BigCommerce, got used to the conversion lift, and then discovered they have to either upgrade to Shopify Plus ($2,300+/month) or find app-based alternatives that don't quite replicate the original behavior.

If checkout customization is critical to your business, factor Plus costs into your migration decision. Or talk to us first — sometimes there's an app-based solution that gets you 85% of the way there on standard Shopify. We evaluate this during our pre-migration scoping call. Our Shopify CRO work often starts at this exact junction.

Your Pre-Launch Migration Checklist

Don't go live without running through this list. These are the steps that catch the expensive mistakes before they go live, not after.

  • Audit product variant counts: Export your full catalog and flag any product with more than 100 variants. Document your restructuring plan for each.
  • Map every URL to a redirect: Build a spreadsheet with source URL (BigCommerce) and destination URL (Shopify) for products, collections, pages, and blog posts.
  • Crawl your BigCommerce store first: Use Screaming Frog or Sitebulb before migration. You need a complete picture of what's indexed and what has inbound links.
  • Export and verify order history: After migration, spot-check 20–30 orders in Shopify against the BigCommerce export. Date, total, line items, customer email — all should match exactly.
  • Build your password reset email flow: Set this up in your email platform before launch. It should go out automatically within an hour of migration going live.
  • Test every payment method on staging: If you're adding Shopify Payments, run test transactions with a real card in test mode. Verify Shop Pay, Apple Pay, and any BNPL options work correctly.
  • Replicate your shipping rules manually: BigCommerce shipping zone logic doesn't migrate. Rebuild each rule in Shopify's shipping settings and verify with a test checkout from multiple zip codes.
  • Check your tax configurations: Especially if you sell into multiple US states or internationally. Shopify's tax engine works differently from BigCommerce's.
  • Verify metafields and custom data: Any custom fields you used in BigCommerce for product specs, sizing guides, or certifications need to be recreated as Shopify metafields and mapped to your theme templates.
  • Set up Google Search Console on the new store: Submit your new sitemap the same day you go live. Monitor for crawl errors daily for the first two weeks post-launch.

Choosing the Right Theme Post-Migration

Don't just buy a theme and swap in your content. Your BigCommerce theme's layout logic may have trained your customers to find things in specific places. Menus, filter placement, product image galleries, trust badges — these things affect conversion rates in ways that are hard to measure until you've lost the revenue.

We strongly recommend doing a structured Shopify theme customization process after migration rather than launching with a generic out-of-the-box theme. You're already disrupting your customers by moving platforms. Make sure the new experience is at least as good as what they had — ideally better. If you're rebuilding the store from the ground up, our Shopify store build service starts with conversion architecture, not just visual design.

Frequently Asked Questions

How long does a BigCommerce to Shopify migration take?

For a store with under 1,000 SKUs and standard checkout needs, a professional migration typically runs 2–4 weeks. That includes pre-migration audit, data transfer, redirect mapping, QA testing, and launch. Larger catalogs, complex integrations (ERP, 3PL, custom APIs), or significant theme work can push that to 6–10 weeks. Anyone promising a full migration in 48 hours is skipping the steps that protect your SEO and conversion rate.

Will I lose my SEO rankings when I move from BigCommerce to Shopify?

You don't have to. Rankings are preserved when redirects are set up correctly, metadata is migrated accurately, and the new site's technical SEO is solid from day one. The stores that lose rankings are almost always ones where redirects were incomplete or the migration was done without an SEO audit. Temporary ranking fluctuations of 2–4 weeks are normal even with a perfect migration — Google needs time to recrawl and reindex the new URLs.

Can I migrate customer order history from BigCommerce to Shopify?

Yes, order history migrates. Historical orders show up in the customer's account under "Orders" in Shopify, and your reporting carries over. What doesn't migrate is the ability to fulfill or edit those historical orders — they come in as archived. For operational purposes, your team should also have view access to the BigCommerce backend for 30–60 days post-migration to look up older order details if needed.

If you're weighing whether to do this migration yourself or bring in a team that's done it dozens of times, the math usually isn't close. One major SEO recovery or checkout rebuild costs more than a professional migration. We handle BigCommerce to Shopify migrations end-to-end — audit, data transfer, redirects, theme setup, and post-launch monitoring — so the risks outlined above don't become your problem at 2am on launch day.