Article · 15 min read

Bottom-Up Sales Forecasting: Formula, Examples, and Process

Weflow Free Intermediate

This is the concrete forecasting method behind the opinionated answer: it walks through pipeline count times win rate times deal size, then upgrades it to stage-weighted probability with a worked example (Discovery 10%, Evaluation 25%, Proposal 50%, Negotiation 70%), so you build a number from your own deal-by-deal reality instead of a top-down fantasy. It also names the trap directly, calling out 'happy ears' and rep sandbagging, which is exactly the vanity pipeline that later contradicts your bank account.

• Forecast by summing each deal weighted by its stage conversion rate, not one blanket win rate, so a fat top-of-funnel does not inflate the total
• Replace the vendor's default stage percentages with your own historical close rates per stage as soon as you have enough closed deals to compute them
• Pipeline hygiene (killing dead deals, fixing stale stages) is the foundation of a forecast you can defend to investors, not busywork