What is Revenue Forecasting?
Revenue forecasting projects future revenue based on current trends, pipeline, and assumptions. Accurate forecasts enable better planning for hiring, spending, and fundraising.
Good forecasts combine bottom-up inputs (pipeline deals, renewal rates) with top-down validation (historical growth rates, market benchmarks).
Why Revenue Forecasting Matters
Accurate forecasts prevent cash crunches and enable confident decision-making. If you know revenue will grow 20%, you can plan hiring accordingly. If forecasts show a shortfall, you can adjust spending before it becomes critical.
Investors expect founders to forecast accurately. Missing forecasts damages credibility. Beating forecasts by huge margins suggests sandbagging.
Building Revenue Forecasts
Start with existing recurring revenue. Add expected new sales from pipeline (adjusted by win rate and timing). Subtract expected churn. Add expansion revenue from upsells. Create multiple scenarios (base, upside, downside) to plan for uncertainty.
How to Build a Revenue Forecast Step by Step
Step 1: Start with your existing recurring revenue base. Your current MRR is the foundation — it's the most reliable part of the forecast.
- Current MRR: $85,000
Step 2: Subtract expected churn. Apply your historical monthly churn rate.
- Monthly churn rate: 3%
- Expected churn: $85K × 0.03 = $2,550/mo
Step 3: Add expected expansion revenue. Use your historical expansion rate from existing customers.
- Monthly expansion rate: 1.5%
- Expected expansion: $85K × 0.015 = $1,275/mo
Step 4: Add expected new customer revenue. Use your pipeline and historical close rates.
- Qualified pipeline: $180K ARR
- Average close rate: 25%
- Average sales cycle: 45 days
- Expected new MRR this month: ($180K × 0.25) ÷ 12 ÷ 1.5 = ~$2,500
Step 5: Calculate next month's forecasted MRR.
- Forecast = $85,000 - $2,550 + $1,275 + $2,500 = $86,225
Step 6: Build three scenarios. Repeat steps 2-5 for 12 months under base, upside (lower churn, more pipeline), and downside (higher churn, fewer closes) assumptions.
Common mistakes founders make:
- Forecasting from a top-down TAM model instead of bottom-up unit economics
- Being overly optimistic about close rates and timing
- Not subtracting churn from the forecast
- Showing investors one number instead of a range with scenarios
Revenue Forecast = Current Revenue + New Revenue - Churned Revenue + Expansion Revenue
Build bottom-up from pipeline and top-down from growth rates
Your SaaS company builds a bottom-up revenue forecast:
- Current MRR: $100,000
- Expected new MRR: $15,000
- Expected churn: ($5,000)
- Expected expansion: $8,000
Next Month Forecast = $100K + $15K - $5K + $8K = $118,000
Repeat for each month, adjusting assumptions based on pipeline and trends.