
Proposed A/B Testing Framework for the Checkout Funnel
2026-04-10
We are losing high-intent users at the final billing step.
Overall checkout conversion is down 2.4% MoM.
Cart abandonment spikes explicitly on the /payment route.
Customer support tickets regarding “promo codes” have doubled.
If we simplify the billing form by hiding the “Discount Code” field behind a clickable link…
Then conversion will increase.
Why? Users are leaving the page to hunt for coupon codes on Google, getting distracted, and failing to return to complete the purchase.
Here is the proposed statistical framework for the test:
Metric
Target
Notes
Primary Metric
Checkout Completion %
Guardrail: AOV
MDE
1.5%
Minimum Detectable Effect
Significance
95% (\(\alpha = 0.05\))
Standard threshold
Power
80% (\(\beta = 0.20\))
Required Traffic: 45,000 users per variant (Approx. 14 days of traffic).
Let’s look at what a successful 1.5% lift means for the bottom line.

Estimated ROI: +$1.2M Annualized
Next Steps {transition=“slide”}
Engineering: Implement the UI toggle for the promo code field (Sprint 4).
Data Science: Configure the split allocation in Optimizely.
Marketing: Ensure active promo codes are communicated via email to prevent cart abandonment.
Questions?