ERP implementation in 90 days — realistic playbook

"90-day ERP rollout" is the standard pitch. In our experience one or two projects out of ten actually hit it. The rest slip — not because the vendor is bad, but because 90 days assume things that aren't always there.

What you actually need on day zero for a real 90-day window:

• Documented sales, warehouse, and procurement processes — not perfect, but written.
• One (just one) decision maker on the customer side with authority to call shots in 24 hours.
• Clean SKU master data. If you have 30k items with three name variants each — forget 90 days.
• Willingness to drop 30% of nice-to-haves. Without that, scope creep eats the timeline.

What 90 days actually looks like: 2 weeks audit and gap analysis, 4 weeks configuration and integrations, 2 weeks data migration and tests, 2 weeks parallel run with corrections.

The biggest trap isn't the ERP itself — it's the integrations. Bank gateway, marketplace, EDI, payment gateway. Each is its own subproject. Most plans don't budget for all of them.