Shipping Cost Per Pound: Complete Rate Guide

Shipping costs don't scale linearly with weight. A 1 lb package might cost $6.25 ($6.25/lb), while a 10 lb package costs $16.80 ($1.68/lb).

This is because carriers have base handling costs regardless of weight. The first 1-2 lbs includes these fixed costs, making lightweight packages disproportionately expensive per pound.

For this reason, combining multiple items into one shipment reduces overall per-pound costs.

Average per-pound costs with commercial rates (Zone 5):

Under 1 lb: $6-8 per lb (base costs dominate)

1-3 lbs: $2.50-$3.50 per pound

3-5 lbs: $2.00-$2.75 per pound

5-10 lbs: $1.50-$2.00 per pound

10-20 lbs: $1.25-$1.75 per pound

20-50 lbs: $1.00-$1.50 per pound

Traditional per-pound thinking breaks down in several scenarios:

Dimensional weight: Large lightweight boxes are priced by dimensions, not actual weight.

Flat rate: USPS Flat Rate boxes charge one price regardless of weight (up to 70 lbs).

Cubic pricing: USPS Cubic charges by package size, not weight - perfect for dense items.