What does “Combined shipping discounts are calculated in the checkout system and are based on a single payment being made at one time for all items.” mean?
Essentially it means that when you buy multiple items and go thru the checkout system for them all at once, you will generally receive a better S&H costs than if you make multiple separate purchases. The checkout system will not recognize that you bought something earlier in the day and give you a lower S&H cost for the item you are now buying. It will be treated as an entirely separate purchase. This will not be corrected later, but continued to be treated as separate purchases even though they may end up being shipped together.
Behind the scenes in the store there is a S&H Matrix. Each item is given a value for the Matrix. This value is based on weight, packaging cost, handling costs and other variables. The Matrix starts at S&H costs value 1, moves to value 2 then moves up values by increments of 2. A multiple item purchase has it’s item values added up to determine the final S&H charge. As an example, value 1 is $3.45 and value 2 is $3.45, so 2 value 1 items would add up to 2 and the S&H charge would be $3.45, not $6.90 (2 x $3.45). Midpoints between values increase to the next Value number. As an example, there is no value 3 increment; the next value after 2 is 4. Value 4 is $3.70, so 3 value 1 items would be $3.70 S&H cost but so would 4 value 1 items.
Note: Some items are inputted with midpoint values and as such adding a value 1 item with them would not increase the S&H cost.
Note: Please don’t try to associate these values solely with weight. Differences in shipping methods and packaging can be very large. For example a paperback book may be shipped via Media Mail for much less then it may be shipped via 1st Class or Priority Mail.