Shopify migration timeline. Week by week.
Discovery, data, theme, apps, QA, launch, and 90-day recovery — the actual week-by-week of a typical mid-market Shopify migration, with the decisions that land each week.
Small 6-8 weeks. Mid-market 10-14. Enterprise 16-24.
A typical mid-market Shopify migration runs 10 to 14 weeks end-to-end across six phases: discovery (weeks 1-2), data migration (3-4), theme rebuild (4-8), app replacement (6-9), QA + launch (9-10), and 90-day recovery (11-14). Small catalogs compress to 6-8 weeks; enterprise Plus migrations stretch to 16-24. The two variables that drive every week of variance are data complexity (custom attributes, subscription records, historical orders) and integration depth (ERP, 3PL, B2B pricing engines). A 2-week discovery phase at the start prices both into the scope; teams that skip discovery usually miss their deadline by 40 to 60 percent.
Fourteen weeks. Each one named.
Discovery kickoff. Stakeholder interviews, GSC URL inventory pull, top-500 ranking keywords exported, plugin audit, custom field inventory, brand-system review. Nothing gets built this week.
Scope sign-off. Requirements document delivered, fixed-price proposal locked, redirect strategy agreed, integrations catalogued. Build does not start without a signed scope document.
Data migration begins. Products, variants, images exported from source. Custom fields mapped to Shopify metafields. First cut imported to a development store for review.
Data QA + theme scaffold. Spot-check 100 random SKUs against source; fix metafield mapping issues. Theme base selected (Dawn, Impulse, or custom). Homepage template scaffold built.
Product + collection templates. PDP rebuilt with metafield bindings. Collection page with filtering. First working demo on staging; client walkthrough.
Cart, checkout, account. Cart drawer, accelerated checkout, customer account pages. Shopify Checkout Extensibility customizations scoped if needed.
App installs. Email provider (Klaviyo typical), reviews app, subscription app if applicable, search, cart upsell. Every app configured with preserved customer + order IDs.
Integrations. ERP, 3PL, accounting, shipping, tax. Webhooks wired. End-to-end order flow tested from checkout through fulfillment.
Redirect map + UAT. Complete 301 redirect map built and reviewed. Full user-acceptance testing across flows. Client + agency + any third parties sign off.
Launch. DNS cutover Tuesday morning (never Friday). Redirects live from minute zero. Sitemap submitted to GSC. War-room Slack active for 48 hours monitoring real traffic.
Week-1 recovery. Daily rank monitoring, CWV + 404 log review, customer-report triage. Small redirect tuning for URLs that missed the map.
Week-2 recovery. Trend watching on GSC impressions + position data. Typical week-2 trajectory: small initial dip closing back up. First monthly report.
Steady-state. Rankings recovered or on recovery trajectory. Conversion rate vs old site compared. Outstanding issue backlog cleared.
Day-90 report. Written recovery report covering rank trajectory, traffic, conversion, and revenue continuity. Project closes or transitions to retainer.
Five answers.
How long does a Shopify migration take?
Six to 24 weeks depending on scope. Small catalog migration with design-as-is adaptation: 6 to 8 weeks. Mid-market migration with custom theme and standard integrations: 10 to 14 weeks. Enterprise Shopify Plus migration with 10,000-plus SKUs, complex B2B, custom checkout, and multi-store: 16 to 24 weeks. The two factors that drive the range are data complexity (product attributes, custom fields, subscription data) and integration depth (ERP, 3PL, accounting, payment). A 2-week discovery phase at the start determines which bucket the project falls into.
Can migrations run faster than 6 weeks?
Technically yes, practically rarely. Under 6 weeks requires a small catalog (under 200 SKUs), design adaptation rather than custom theme, no integrations beyond Shopify Payments and a basic email tool, and a team that can review demos on a daily cadence. The work is the same; compressing the calendar means parallelizing everything with minimal client review checkpoints. Stores attempting sub-6-week migrations often end up with broken redirects or missed data because the compression usually comes out of the audit and QA phases where it should not.
What determines timeline variance?
Four factors. One, product data complexity: a 500-SKU catalog with simple variants takes 1 week of data work; a 10,000-SKU catalog with 40 custom attributes takes 3 weeks. Two, theme approach: design-as-is adaptation takes 3 weeks; custom design from wireframes takes 8 weeks. Three, integrations: every non-standard integration (ERP, 3PL, multi-warehouse inventory, B2B pricing engine) adds 1 to 3 weeks. Four, client review pace: same-day sign-offs keep things moving; week-long reviews add weeks cumulatively. The discovery sprint sizes all four before build starts.
When does SEO preservation work happen?
Throughout the build, with a concentrated push in the two weeks before launch. Weeks 1-2: full URL inventory pull from Google Search Console and ranking keyword export per page. Weeks 3-8: as each template is rebuilt, title tags, meta descriptions, H1s, and on-page content for ranking pages are carried forward verbatim from the source. Weeks 9-10: 301 redirect map built and tested. Launch week: redirects deployed live on day 0. Weeks 11-14: daily rank monitoring, GSC error alerts, recovery tuning. SEO work is the 90-day period, not a single week's task.
What happens after launch week?
Week 1 post-launch: daily rank and Core Web Vitals monitoring, daily 404 log review, bug-triage for anything surfacing from the wider customer base. Week 2-4: trend watching on GSC coverage, impressions, and position data; small redirect tuning for URLs that missed the original map. Week 5-12: monthly written status covering rank recovery, conversion rate on new site vs old, revenue continuity, and any outstanding issues. Day 90: formal recovery report closing the project or transitioning to an ongoing retainer for continuous optimization work.