Most merchants pick a free shipping threshold the way they pick a logo color — a number that feels right, gets rounded to something clean like $50 or $75, and then never gets revisited. The progress bar that shows shoppers how close they are to hitting it is a well-known conversion tool at this point. What's talked about far less is the number itself, and getting that number wrong quietly caps how much the whole tactic can do for you.
Set the threshold too low and you're giving away shipping on orders that would have converted anyway. Set it too high and shoppers never believe they can reach it, so the incentive does nothing. The right number sits in a fairly narrow range, and finding it takes a bit of arithmetic most merchants skip.
Start with your actual average order value, not a guess
The most common mistake is picking a threshold based on a competitor's number or a round figure that sounds reasonable. Instead, start with your store's real AOV, pulled from the last 60–90 days of order data.
A threshold set even slightly above current AOV gives shoppers something to reach for. A threshold set at or below current AOV gives shipping away for free on purchases that were already going to happen, since most shoppers were already spending that much.
A commonly used starting formula:
- Threshold = current AOV × 1.15 to 1.30
If your average order is $62, a threshold somewhere between $71 and $81 gives shoppers a believable stretch goal without being so far out of reach that they give up and check out anyway without adding anything.
Why the gap matters more than the number itself
Shoppers respond to the distance between what's in their cart and the threshold, not the threshold in isolation. A $75 threshold feels completely different to a shopper with $68 in their cart than to one with $22 in their cart.
- A gap under $15–20 tends to feel achievable — close enough that adding one more item makes sense.
- A gap over $30–40 tends to feel like a stretch not worth bothering with, especially if the shopper doesn't have an obvious product in mind to fill it.
This is part of why a single fixed threshold works better for some traffic segments than others. Shoppers arriving from a discount-heavy email campaign often land with smaller carts, meaning the gap to a $75 threshold might read as too far to close. Shoppers browsing full-price collection pages tend to land with larger carts already, meaning the same threshold might feel almost already met.
The margin math behind the number
The threshold isn't just a psychology question — it's a cost question. Free shipping isn't free; it's a cost you're absorbing in exchange for a larger order. The math needs to work in your favor.
A simple way to check this: compare your average shipping cost per order against your average margin per additional dollar of cart value.
- If your average shipping cost is $8 and your average margin is roughly 40%, a shopper needs to add about $20 in additional product for the shipping giveaway to break even on margin alone, before counting any lift in likelihood to convert at all.
- If your threshold gap is smaller than that break-even amount, you may be giving away shipping on orders that don't generate enough extra margin to cover it.
- If your threshold gap is larger than that, you're likely fine on margin, but you may be setting the bar too far away for shoppers to bother closing it.
Running this calculation once, even roughly, tends to reveal whether a merchant's threshold is generous because it's strategic or generous because it was never checked against the shipping cost it's supposed to offset.
Test more than one threshold before settling
Most stores land on their threshold once and leave it for years. A short test comparing two or three thresholds against each other, run over a few weeks, usually surfaces a clearer answer than guessing:
- Test a threshold close to current AOV (a small stretch) against one noticeably higher (a bigger stretch), and compare both average order value and how often shoppers actually reach the threshold rather than abandoning short of it.
- Watch the abandonment rate specifically among shoppers who got within a few dollars of the threshold and didn't cross it. A high number here suggests the gap was too large for the products available, or that the cart wasn't surfacing an easy way to close it.
- Segment new versus returning customers if your traffic supports it. Returning customers who already know your average pricing tend to respond to a different threshold than new visitors who haven't calibrated their expectations yet.
Multiple thresholds instead of one flat number
Some merchants get more mileage out of a tiered structure than a single cutoff — free shipping at one level, a small gift or discount at a slightly higher level, and a bigger perk at the top. This spreads the incentive across a wider range of cart sizes instead of concentrating it all at one number that only helps shoppers already close to it.
A tiered structure also gives the cart drawer more to say. Instead of one static message, the progress bar can update with a different reward at each stage, which keeps the incentive relevant whether a shopper has $20 or $90 in their cart. Apps like Revenix Cart Upsell support multi-tier thresholds inside the cart drawer for merchants who want to test this without rebuilding their theme, though the underlying math — knowing your AOV, your shipping cost, and your margin before picking the numbers — matters regardless of which tool displays it.
Revisit the number as your store changes
A threshold set correctly at launch can drift out of alignment as pricing, product mix, or shipping costs change. A round of price increases that lifts AOV without a corresponding threshold adjustment quietly turns a stretch goal back into a giveaway on orders that were already above it. Carriers raising shipping rates has the same effect from the cost side — the margin math that justified the threshold a year ago may no longer hold.
A quick quarterly check — current AOV, current average shipping cost, current threshold — is usually enough to catch drift before it erodes margin or lets the incentive go stale.
The takeaway
The free shipping threshold gets treated as a fixed input, but it's really a number that should be calculated and revisited, not guessed once and forgotten. Anchoring it to your actual AOV, checking it against your shipping cost and margin, and testing the gap shoppers actually need to close are the difference between a threshold that quietly drives AOV up and one that either gives away shipping for nothing or sits too far out of reach to matter. If your store's threshold has never been recalculated since launch, it's worth the ten minutes of math to see if the number still makes sense.