Move to Shopify from any platform, rankings and order history intact.

Ask to see how they built and validated the redirect map on a previous migration — not a screenshot, the actual method. Ask who owns the outcome if organic traffic drops in week three. Ask what happens to custom functionality that has no native Shopify equivalent, and whether the quote covers rebuilding it or only moving data. Any partner who quotes a fixed price before seeing your catalogue, your custom logic, and your integration list is guessing, and the gap will surface as change requests later.

Three things, in rough order of frequency and damage. Incomplete redirect maps that catch the top 50 URLs and quietly drop the long tail — blog posts, filtered collection URLs, old campaign landing pages. Custom logic assumed to be data when it is actually code: B2B pricing tiers, bundle rules, complex tax or shipping conditions. And integration gaps, where the ERP, 3PL, or accounting sync gets scoped last and becomes the reason go-live slips by a month.

Not the number of products, mostly. Cost tracks catalogue irregularity — how clean and consistent your data is — plus the volume of custom functionality with no native Shopify equivalent, the number of live integrations that must keep working, and how much design work you fold in at the same time. A 20,000-SKU catalogue with clean, consistent data is often cheaper to move than a 400-SKU store carrying bespoke pricing logic and three homegrown integrations.

Sometimes, but understand the trade-off. Doing both together means one disruption and one budget, but if traffic or conversion moves after launch you cannot separate the platform change from the design change. Migrating on a close-to-current design first gives you a clean before-and-after, then you redesign against a measured baseline. We recommend the combined approach mainly when the existing design is itself a primary reason for moving.

Most mid-sized migrations run four to ten weeks from audit to cutover. The audit and field-mapping phase almost always takes longer than clients expect; the cutover itself takes hours. Complex catalogues, B2B logic, subscriptions, or ERP integration extend it. We set the timeline at scoping and share it as a dated plan with named dependencies rather than a range, because a range is how migrations drift.

Three things. Crawl errors and 404s in Search Console, checked weekly for the first eight weeks — that is where an incomplete redirect map reveals itself. Rankings for your top revenue URLs, expecting some volatility before recovery rather than an instant match. And Core Web Vitals plus checkout completion rate, because post-migration app installs are the single most common reason a fast new store is slow again six months later.

Yes. We publish dedicated guides for eight source platforms, and migrations from custom or in-house systems follow the same process: audit, field mapping, staging build, redirect map, QA and test orders, cutover. The less standard the source platform, the more the audit phase matters, because there is no off-the-shelf exporter to lean on and every field mapping has to be established by inspection.