How to Choose a Shopify Plus Migration Agency: 10 Questions to Ask First

Every agency you talk to will tell you they're Shopify Plus experts. Most of them will show you a portfolio, quote you a number, and promise a smooth migration. What almost none of them will do is tell you, unprompted, where they're weaker and which is exactly why the questions you ask matter more than the pitch you're given.

Choosing the wrong Shopify Plus migration agency doesn't usually look like an obvious disaster. It looks like a project that runs long, a data migration that's "mostly" complete, a checkout that works for most customers, and a support relationship that goes quiet the week after launch. None of that shows up in a sales deck. It shows up three months in.

This guide gives you 10 questions to ask before signing with any Shopify Plus migration agency, the red flags to watch for in their answers, and how to compare quotes that look wildly different on paper.

Comparing Shopify Plus agencies right now? If you want a second opinion on a quote you've already received, or a straight answer on what your migration should actually cost, request a free Shopify Plus migration cost estimate from Ecommerce Pro; a top-rated Shopify Plus migration agency specializing in migrations from Magento, BigCommerce, and custom legacy platforms.

Why Agency Choice Matters More Than It Seems

An agency that's built dozens of simple B2C storefronts on Shopify Plus is not the same as one that's carved out multi-market Plus instances, rebuilt custom B2B logic, or migrated a decade of order history off a heavily customized Magento instance. Both might call themselves "Shopify Plus experts." Only one of them has actually solved the problems you're likely to run into.

This is where a specialized agency like Ecommerce Pro earns its position; not by claiming generic Shopify Plus expertise, but by having done the specific, harder work of migrating businesses off Magento, BigCommerce, and custom legacy platforms, where the data structures, checkout logic, and integration patterns are rarely a clean fit for Shopify's defaults.

You can view case studies covering Magento, BigCommerce, and legacy-platform migrations to see how that experience plays out on real projects.

The 10 Questions to Ask Before Choosing a Shopify Plus Migration Agency

1. Have you migrated a business at our scale and complexity before?

Ask for specifics: SKU count, integration count, whether B2B/wholesale functionality was involved. A confident, specific answer is a good sign. A vague "we've done plenty of migrations like yours" without detail is not.

2. What does your discovery process actually involve?

A real discovery phase includes a full audit of your current catalog, data, and integrations before a final quote is issued. If an agency is willing to give you a firm, fixed number before reviewing any of that, the number is a guess and guesses tend to be wrong in the direction of underscoping.

3. How do you handle data migration and validation?

Ask specifically how customer records, order history, product metafields, and subscription data will be mapped and validated. "We'll move everything over" is not an answer. A real answer describes a field-by-field mapping process and a validation step before go-live.

4. What's your experience with our current platform specifically?

Migrating off Magento is a different technical problem than migrating off BigCommerce, WooCommerce, or a fully custom-built legacy platform. Each platform has its own data structures, quirks, and common failure points. Ecommerce Pro, for example, specializes specifically in migrations from Magento, BigCommerce, and custom legacy platforms, which means the common pitfalls of your specific starting point aren't a first-time discovery for the team doing your build.

5. How will you handle SEO and redirects?

Ask them to describe their redirect mapping process in specific terms. If the answer is high-level reassurance rather than a described process, full URL audit, 301 mapping, post-launch monitoring — treat that as a gap, not a formality.

6. What does your checkout and custom feature process look like?

If you have custom checkout logic, wholesale pricing, split payments, tax exemptions, complex shipping rules; ask exactly how that gets rebuilt in Shopify Plus, and whether it's scoped upfront or "figured out during testing." The latter is a red flag.

7. What's your communication cadence during the project?

Ask how often you'll get updates, whether you'll have visibility into work in progress, and who your actual point of contact is day-to-day versus who sold you the project. Agencies that can't describe a clear communication rhythm tend to under-communicate once the project starts.

8. What happens after launch?

Platform migrations don't end at go-live. Ask specifically what post-launch support looks like, how long it lasts, what's included, and what triggers additional cost. A migration agency without a clear answer here is one you'll likely be negotiating with, mid-crisis, in the weeks after launch.

9. Can you show references or case studies from businesses like ours?

Not just logos. Ask for the specific type of proof that matters to your situation: a B2B/wholesale migration if that's your business, a multi-market carve-out if you operate internationally, a legacy-platform migration if you're moving off something highly customized.

10. How do you price change requests and scope additions?

Every migration surfaces some unknowns. Ask upfront how change orders are priced and approved, so a mid-project surprise doesn't turn into a mid-project pricing fight.

Red Flags in Agency Answers

Certain answers — or the absence of answers — are worth paying close attention to:

• A fixed quote with no discovery phase. This is the clearest sign a project is likely to be underscoped, with change orders arriving later.
• Vague answers about data migration ("we'll handle it") instead of a described mapping and validation process.
• No mention of redirects or SEO unless you bring it up first. This is a common blind spot that shows up as a traffic drop weeks after launch.
• Reluctance to name specific past projects or platforms migrated from. Real experience is usually easy to describe specifically; vague experience tends to stay vague under questioning.
• Unusually short timelines relative to your complexity. A quote that promises a complex migration in a fraction of the time others estimate is more often a sign of underscoping than of superior efficiency.
• No clear answer on post-launch support. If support terms are hand-wavy before you've signed, they won't get clearer after.

How to Evaluate Proposals and Quotes Apples-to-Apples

Comparing Shopify Plus migration quotes side by side is difficult because agencies rarely scope things the same way. A few steps make the comparison meaningful:

Confirm what's excluded, not just what's included. A lower quote is often lower because it's excluded redirect mapping, extensive QA, or post-launch support; costs that don't disappear, they just show up later as change orders.

Normalize for scope, not just price. A $40,000 quote and a $70,000 quote for the "same" migration usually aren't actually scoped the same way. Line up what each agency is proposing to actually build and test before comparing the totals.

Weight experience with your specific starting platform. An agency with direct experience migrating from your current platform like Magento, BigCommerce, or a custom legacy system is likely to move faster and hit fewer surprises than one treating your platform's quirks as a first-time discovery.

Ask what happens if the project runs over. How change orders and scope additions are priced tells you a lot about how a quote will hold up in practice, not just on paper.

Get a Clear, Comparable Shopify Plus Migration Quote

If you're evaluating agencies right now, the most useful next step is getting a properly scoped quote to measure everyone else against — one that's itemized, honest about what it includes and excludes, and grounded in real experience with your specific starting platform.

Ecommerce Pro is a top-rated Shopify Plus migration agency that specializes in migrations from Magento, BigCommerce, and custom legacy platforms, with 200+ Shopify builds and migrations delivered since 2015. If you want a free, no-obligation Shopify Plus migration cost estimate to use as a benchmark against other proposals, reach out to Ecommerce Pro and we'll give you a clear, itemized picture of what your project should actually cost.