# Testing a Free Shipping Progress Bar in the Cart

Page: https://alidemirbas.com.tr/en/lab/ab-test-library/tests/testing-a-free-shipping-progress-bar-in-the-cart

## Hypothesis

Seeing in the cart how much more they need to spend for free shipping may prompt some shoppers to add one more item to cross the threshold. The likely gain is a higher average order value (AOV), especially among carts that sit just below it.

## When to run this test

Order value data with carts piling up just below the free-shipping threshold, or surveys and support tickets showing that shoppers do not know the condition, are the signals that justify this test. When the bar works, carts near the threshold get more add-to-carts and more orders land above it, while order completion holds. If shoppers know the threshold and still leave at the shipping fee, the fee itself may be the problem, so look at that first. If the threshold or promotion terms will change during the test, postpone it, since you cannot isolate the bar's effect while the threshold moves.

## Primary metric

**Average order value (AOV)**: Compare revenue per completed order. Because AOV includes buyers only, read it alongside order completion and revenue per visitor.

## Other metrics

- **Add-to-cart rate**: Check whether seeing the free-shipping threshold changes add-to-cart.
- **Order completion rate**: Track order completion among assigned visitors as cart value changes.
- **Revenue per visitor (RPV)**: Compare revenue per assigned visitor, whether or not they purchase.

## What to check before and during the test

- **Change**: Add a progress bar showing the amount remaining to reach free shipping in the variant only.
- **Keep constant**: Keep the shipping threshold, product prices, promotions and message logic the same in both arms.
- **Cart behavior**: Track both items added and removed to understand how the threshold message affects cart changes.
- **Orders and revenue**: Read AOV alongside order completion and revenue per visitor.
- **Device**: Check that the bar renders correctly and does not obstruct the cart flow on mobile or desktop.

## What to watch when reading the result

- An AOV gain counts only if order completion and revenue per visitor do not fall. If either drops, larger carts may be coming from fewer orders, so do not call the result a success.
- This finding is tied to this threshold, message and placement; test color, message or position changes separately. Check that the message updates correctly once the cart reaches or passes the threshold. Place the bar so it neither covers the main CTA nor pushes it down; otherwise the result reflects the placement rather than the bar itself.
- When AOV barely moves, look at items added and removed together; the threshold message may lead some shoppers to add items and others to remove them, and the two can cancel out. Before drawing conclusions, confirm that each arm received its planned share of visitors (sample ratio mismatch). The [A/B test significance calculator](https://alidemirbas.com.tr/en/calculators/ab-test) shows whether the add-to-cart rate gap could be due to chance; AOV is an average it does not test, so read that gap with the same caution.

## Frequently Asked Questions

### Does a higher average order value mean the shipping bar worked?

AOV covers completed orders only. Use it as the primary outcome while checking order completion and revenue per visitor as guardrails. Larger orders can coexist with fewer purchases, so the increase alone is insufficient.

### Can a free-shipping progress bar also encourage item removal?

It can affect both additions and removals. Track both rather than assuming every change increases basket size. Update the message correctly when the cart reaches or exceeds the threshold.

### Where should the free-shipping bar go in the cart?

Place it where it does not cover or displace the main CTA. Check the cart flow on mobile and desktop. Keep the selected message, color and placement stable during this comparison.