Free Shipping Thresholds: The Break-Even Math Before You Set the Number
The threshold is a trade, not a perk
Free shipping is the single biggest lever on conversion that a merchandiser controls, and it is also the easiest way to give away margin without noticing. Baymard's research puts extra costs, shipping and fees, at the top of the abandonment list, with 40 to 48 percent of shoppers naming it as the reason they left. A threshold that is too high does nothing: the shopper sees it, does the math, and leaves anyway. A threshold that is too low converts the same orders you would have had, and pays the shipping on all of them.
The median threshold among US retailers is $64, according to a 2024 survey. That number is a useful anchor and a useless target, because your threshold has to be set from your own average order value and your own margin, not from the median store. A store with a $30 average order and a store with a $150 average order should not share a threshold, and the store that copies the median is the one that pays for it.
The break-even check
The arithmetic is one line. Take the incremental spend the threshold asks for, multiply by your gross margin, and compare the result with the average shipping cost. (Threshold minus AOV) times gross margin must be greater than or equal to the average shipping cost. At an average order of $62, a 55 percent gross margin, and $7.50 average shipping, the threshold lands near $80: the $18 of incremental spend earns $9.90 of margin, which covers the $7.50 shipping and leaves a little room. Below that line, the threshold buys orders and loses money on each one.
The second number to watch is the lift. Track the share of orders that land between your old average and the new threshold, and the share that would have landed there anyway. If the threshold moved average order value up by 10 percent and conversion held, it works. If average order value moved up and conversion fell by the same amount, you traded customers for a bigger basket, and the trade usually loses. Watch both numbers for at least two weeks before you declare a result.
What to do when the math says no
When the break-even says the threshold cannot pay, the answer is not to set it anyway and hope. Offer free shipping on a subset: the hero product, the category with the highest margin, or orders above a threshold that the math actually supports. Or subsidize the shipping in the price, which is the same trade made visible: the customer pays a little more per item and sees free shipping, and you know exactly what it costs you. What you do not do is set a $50 threshold on a $30 average order at 40 percent margin and wonder why the quarter went red.
Thresholds also drift. Average order value moves with the assortment, shipping costs move with the carriers, and a threshold set in January can be underwater by June. Re-run the break-even quarterly, and re-run it the week a carrier raises rates. For the pricing side of the same problem, how to price a bundle without giving away the margin covers the arithmetic on the other lever, and the 90-day rule for dead stock explains what to do with the inventory the threshold was supposed to move.
Frequently asked questions
How do I set a free shipping threshold?
Start 20 to 30 percent above your average order value, then check the break-even: the extra margin on the incremental spend above the threshold must cover the average shipping cost. At a $62 average order, 55 percent margin, and $7.50 shipping, the threshold lands near $80.
What is the median free shipping threshold in the US?
About $64, according to a 2024 survey. Use it as an anchor, not a target: your threshold has to come from your own average order value and margin, not the median store.
Why does my free shipping threshold lose money?
Because the threshold is below the break-even point. If (threshold minus AOV) times gross margin is less than the average shipping cost, every order that reaches the threshold loses money on the shipping you just gave away.
Should I offer free shipping on everything?
Only if the margin supports it. Free shipping on a low-margin, low-value assortment turns every order into a loss. Offer it on a subset, the hero product or the highest-margin category, or subsidize it in the price so you know what it costs.