Most teams that try to move from spreadsheets to a CRM fail quietly. A deal slips through the cracks. Two versions of the same contact exist. A rep opens the old sheet out of habit and updates it instead of the new system. Six months later, you're running both in parallel, paying for software nobody trusts, and your sales leader can't tell you where the pipeline actually is. The difference between a clean migration and a slow-motion disaster is not technology—it's a structured handoff process. This guide maps a realistic 90-day path that works for teams of 5 to 50 people. The timeline assumes you're migrating from a core spreadsheet (Google Sheets or Excel) into a real CRM with a proper pipeline, contact dedupe, and deal tracking . If your data is already fragmented across three sheets and a salesperson's email, add two weeks. Weeks 1–2: Audit and deduplication Before you migrate anything, you need to know what you're moving. Most teams skip this and regret it immediately. Pull a full export of your live spreadsheet. Include every column, every tab, every 'archive' sheet someone created and forgot about. Add a timestamp so you know this is your baseline. Count records by type. How many unique contacts? How many deals? How many are orphaned (no contact associated)? You'll find 10–30% data quality issues in this step alone. Identify duplicates. Look for the same company name spelled three ways. Same email with different cases. Same phone number tied to two contact records. In a spreadsheet, duplicates hide because there's no enforced schema. A CRM will scream about them on day one. Document deal stages and status values. How do your reps actually describe a deal? 'Proposal sent', 'Waiting for budget approval', 'Lost—price too high'? Write these down. You'll map them to your CRM's pipeline stages in week 4. List every field and who owns it. If your sheet has 40 columns and nobody knows what half of them mean, this is the moment to clean house. Migrate only fields that drive actual business decisions or legal compliance. Everything else creates maintenance debt. This phase is unglamorous but non-negotiable. A team that spends two weeks on hygiene cuts their cutover time by half. Weeks 3–4: Pilot group and training Pick your best, most adaptable rep. Not your top closer—someone who asks good questions and won't silently revert to the spreadsheet when they're confused. Ideally two reps, or three if you have a dedicated sales ops person who can shadow. In your chosen CRM, set up: A real pipeline that matches how deals move through your business. Not generic 'lead, qualified, proposal, closed'—the stages your team actually uses. Automations that trigger reminders when a deal hasn't moved in 7 days, or when a follow-up is overdue. Show your pilot group that the system helps them, not just reports on them. A search and filter setup that lets them find deals by company, stage, or owner in under 10 seconds. If searching is slow or clunky, reps will open the spreadsheet instead. Run a two-week mini-migration with your pilot group. Load 20–30% of your live deals (not demo data). Let them live in both the spreadsheet and the CRM at the same time. This is intentional redundancy. You're learning which tasks feel natural in the CRM and which ones feel backwards. Collect feedback weekly. Expect at least one task the CRM handles worse than your spreadsheet. Don't pretend it doesn't exist. Either find a workaround, add a workflow to the CRM, or accept that you'll do that one thing manually. By the end of week 4, your pilot group should be able to: Log in without help. Find a deal and update its stage in under 60 seconds. Add a new contact and link it to an existing company without duplication. Explain to a peer why the CRM is better than the spreadsheet for at least one task. Weeks 5–8: Full migration and cutover This is where deals vanish if you're not disciplined. Three days before cutover, freeze the spreadsheet. Announce that no new deals will be entered into it. All updates stop. This prevents the nightmare where a deal gets updated in the old sheet after you've already migrated it to the new one, and nobody knows which version is real. Run your migration in batches: Week 5: Move closed deals and deals over 60 days old. These are stable. They're not going to change. Migrate them, spot-check 5–10%, move on. This builds confidence that the system works. Week 6: Move mid-stage deals (proposal sent, negotiation, waiting for approval). These are the meat of the migration. Assign each deal to the rep who owns it. Make sure the deal value, stage, and expected close date are visible and accurate. Run a spot-check audit: pick 15 random deals and verify the data against the spreadsheet. If error rate is above 3%, stop and fix the import logic. Week 7: Move early-stage deals and leads. These move fast and change often, so the migration window is tighter. Ask your pilot group to help verify that their own deals mapped correctly. This