Conversion Optimization
How to set a free shipping threshold
In short
You set a free shipping threshold by combining your order value distribution, contribution margin and shipping cost per order. The core rule: the margin on what customers add to reach the threshold must cover the shipping cost you absorb. That usually means placing the threshold above your current average order value and validating it with a test.
Contents
- How do you set a free shipping threshold?
- Why does shipping cost matter so much?
- What data do you need?
- How do you calculate the break even point?
- How do different thresholds change profitability?
- How do you choose a threshold in practice?
- How do you test a free shipping threshold?
- What are the alternatives to free shipping?
- Where should the threshold be shown?
- Key takeaways
How do you set a free shipping threshold?
You set a free shipping threshold by working out your order value distribution, contribution margin and shipping cost per order together. The margin earned on what shoppers add to reach the threshold has to cover the shipping cost the store absorbs. So the threshold usually sits above your current average order value and must be validated with a test.
Free shipping is both a conversion tool and a cost line. A well set threshold grows baskets and reduces abandonment. A badly set one hands free shipping to customers who would have bought anyway and quietly eats your margin. This guide shows how to set the threshold with math rather than guesswork.
Why does shipping cost matter so much?
In Baymard Institute's abandonment research, once "just browsing" is excluded, 40% of shoppers said they did not complete an order because extra costs such as shipping, taxes and fees were too high. Another 12% left because they could not see the total cost up front. Shipping affects the decision both through its amount and through when it is shown.
A threshold turns that cost from a penalty into a goal: "I have to pay 5 EUR shipping" becomes "if I add one more 7 EUR item, shipping is free".
What data do you need?
Gather four inputs before you calculate anything:
- Order value distribution: where orders cluster over the last three to six months. The average alone is not enough; look at the median and the spread.
- Average shipping cost per order: the real cost based on weight, zones and your carrier rates.
- Contribution margin: what remains of the selling price after product cost, payment fees and packaging.
- Current shipping policy: what do you charge customers today?
How do you calculate the break even point?
The core formula: minimum extra basket value needed = shipping cost / contribution margin.
Example: a store pays 5 EUR shipping per order and has a 40% contribution margin. 5 / 0.40 = 12.50 EUR. Every customer whose shipping you absorb needs to add at least 12.50 EUR of products on average to cover that cost. If they add less, the gap has to be closed by higher conversion or higher customer value.
How do different thresholds change profitability?
Assume the same store has a 36 EUR average order value and currently charges customers 5 EUR for shipping. The table below is an example scenario showing what a customer with a typical 36 EUR basket does at different thresholds.
| Threshold | Customer adds | Extra contribution (40%) | Shipping revenue lost | Net effect per order |
|---|---|---|---|---|
| 30 EUR | 0 EUR | 0 EUR | 5 EUR | -5.00 EUR |
| 42 EUR | 6 EUR | 2.40 EUR | 5 EUR | -2.60 EUR |
| 50 EUR | 14 EUR | 5.60 EUR | 5 EUR | +0.60 EUR |
The table makes one thing clear: a threshold below the average basket means absorbing shipping without earning anything back. Once the threshold sits far enough above the average, basket growth starts to cover the cost.
But the table is only half the story. The higher the threshold, the fewer customers try to reach it, and a threshold that is too high motivates nobody. Free shipping can also lift conversion and turn hesitant shoppers into buyers even if they never reach the threshold. Only a test can measure both effects.
How do you choose a threshold in practice?
- Split your order value distribution into small bands, for example 5 EUR steps.
- Pick a candidate range above the average and median basket, close to the break even add on.
- Count how many orders sit just below that range; the denser the cluster near the threshold, the more effective it will be.
- Make sure you have affordable items that close the gap. If a customer is 4 EUR short and you have nothing between 3 and 7 EUR to suggest, the threshold will not work.
- Test two or three candidate thresholds.
How do you test a free shipping threshold?
Threshold tests resemble price tests and need careful design:
- Server side A/B test: randomly assign visitors to different thresholds. Technically the most reliable route, but make sure the same customer does not see different thresholds across devices.
- Period comparison: change the threshold for a set period and compare it to the previous one. Easy to run, but promotions and seasonality can distort the result.
- Channel test: try the new threshold first on the landing page of a specific ad campaign.
Do not judge success on AOV alone. The best metric is contribution margin per visitor: the profit each visitor leaves after shipping costs. It captures the combined effect of conversion rate, AOV and shipping cost in one number.
What are the alternatives to free shipping?
- Discounted shipping: a token fee below the threshold, free above it.
- Tiered thresholds: reduced shipping at one level, free shipping at a higher one.
- Free shipping for members or repeat orders: encourages loyalty.
- Building shipping into prices: free shipping on every order with prices adjusted accordingly. Weigh this carefully against competitor pricing.
- Gift threshold: a low cost gift above the threshold instead of free shipping.
Where should the threshold be shown?
A threshold only works when people see it. Show it in the announcement bar, under the price on product pages and in the cart. A progress bar in the cart showing the remaining amount, plus suggestions that close the gap, is the most effective placement. Show your shipping terms in Google too: Google Search Central's merchant listing structured data lets you specify shipping cost and delivery time in product markup, so your free shipping offer can surface in search results.
For tactics to recover shoppers who still leave, see our guide to reducing cart abandonment.
Shipping cost also feeds straight into ad profitability. Use our break even ROAS guide to set target ROAS from a margin that includes shipping.
If you would like to run the threshold math on your own order data together, you can book a free growth analysis with the Performetic team through our contact page.
Key takeaways
- Set the threshold from order distribution, contribution margin and shipping cost together.
- Break even extra basket value = shipping cost / contribution margin.
- Thresholds below the average basket usually add cost without adding profit.
- Test thresholds against contribution margin per visitor, not AOV alone.
- Make the threshold visible in the announcement bar, on product pages and with a cart progress bar.
Frequently asked questions
Should the free shipping threshold be above average order value?
Usually, yes. A threshold below the average basket gives free shipping to customers who would have spent that amount anyway. Place it above the average, at a level shoppers can reach by adding an item, where the margin on the added amount covers the shipping cost.
How do you calculate the break even add on value?
Divide your shipping cost per order by your contribution margin. With a 5 EUR shipping cost and a 40% margin, customers need to add at least 12.50 EUR on average. Any shortfall below that has to be recovered through higher conversion.
How do you test a free shipping threshold?
The most reliable approach is a server side A/B test that randomly shows different thresholds to visitors. If that is not possible, run a controlled period comparison. Use contribution margin per visitor, after shipping costs, as the success metric.
Does free shipping on every order make sense?
It can work for high margin, high basket brands, but for most stores it means building shipping into product prices. In that case, check how your prices compare with competitors. Middle ground options such as discounted shipping or tiered thresholds are usually more balanced.