The simple formula
Voice AI ROI = ((calls captured) × (close rate) × (ticket value)) − (system cost)
Compare to baseline: same formula at pre-deployment numbers.
What to track
- Call pickup rate (before vs after)
- Calls captured (volume answered live)
- Booking conversion rate (call → booked appointment)
- Average ticket value
- Cost per call (system fee ÷ call volume)
Attribution challenges
- Calls that would have been missed → 100% attributable to voice AI
- Calls that would have been answered live → measure incremental conversion lift
- After-hours calls → almost always 100% attributable
Real example: dental practice
Pre-deployment: 50 missed calls/month, $250 average ticket, 30% close rate = $3,750 missed monthly revenue. Post-deployment: 90% pickup rate, 30 of those captured calls book = $2,250 recovered. System cost: $400/month. Net ROI: $1,850/month or 4.6x.
Frequently Asked Questions
- How long until I see ROI?
- Most deployments show positive monthly ROI within 30–60 days of launch. Cumulative ROI compounds month over month.