The free shipping threshold trick

People hate paying for shipping more than they hate paying for the product. It's irrational but consistent. A $50 item with $5 shipping feels worse than a $55 item with free shipping.

Set your free shipping threshold just above your current average order value. If your AOV is $40, offer free shipping at $49. Customers who were going to spend $40 will add a $12 item to hit $49 instead of paying $6 for shipping.

The math works in your favor almost every time. You lose the shipping revenue on some orders but gain significantly more in product margin from the upsell. Most retailers who test this see AOV increase 10-15%.

Show the threshold everywhere. In the cart: "You're $12 away from free shipping." In the header: "Free shipping over $49." The reminder does the selling for you.