Most mid-market migrations run 8–16 weeks after audit. Audit, parallel build/data/SEO, QA, and stabilisation each have distinct durations — timeline without scope is a guess.
- Audit and planning: 1–2 weeks.
- Theme + data + SEO run in parallel: 4–10 weeks.
- Large catalogs, ERP, and subscriptions add 4–8 weeks.
- Peak retail seasons constrain launch windows.
Buyers often hear “6–8 weeks” as a default answer. That can be accurate for a focused replatform — but only after scope is defined. Without an audit, timelines are guesses.
Standard timeline by phase
- Audit and planning: 1–2 weeks
- Design and theme build: 3–6 weeks (parallel with data work)
- Data migration and QA: 2–4 weeks
- SEO, redirects, integrations: 1–3 weeks
- Launch and stabilisation: 1 week intensive, 2–4 weeks monitoring
What extends timelines
Large catalogues with inconsistent attribute data, custom subscription logic, multi-store rollouts, and ERP dependencies routinely add four to eight weeks. Peak retail seasons (Q4 in US/UK, EOFY in Australia) also constrain launch windows.
What compresses timelines
Clean product data exports, approved design direction early, a single decision-maker, and a staging store with realistic test orders reduce rework loops and calendar time.
Parallel workstreams
Professional migrations run theme development, app selection, and data mapping concurrently. Sequential “migrate then design” approaches double calendar time and increase downtime risk.
Questions about this topic
Why do agencies say 6–8 weeks?
That assumes small scope, clean data, and parallel workstreams already planned — rarely true without audit.
What adds the most calendar time?
ERP integration, subscription migration, multi-store rollouts, and design revision loops.
Can timeline compress without cutting scope?
Yes — with early design approval, single decision-maker, and staging-first QA.
Get a timeline for your store
Audit returns a phased calendar with dependencies — not a generic week count.
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