Stackable Shipping: How to choose an Add-on shipping profile

This article will outline how to choose a Shipping Profile based on some commonly used shipping fee structures.

Choosing a Shipping Profile

When attempting to decide how to account for add-on shipping costs, there are a number of things to consider:

• Do you want to charge extra for additional items on top of pledge level shipping?
• Do you know the weights of your items yet?
• Will all items be shipped together?
• How much time do you want to invest in setting up or researching shipping?
• How accurate can you afford to be or not to be? 

For everyone, the answers to these questions can vary drastically, so we have made available a variety of ways to charge extra shipping for add-ons. 

Per-Item Shipping Profile

Flat fee applies to each selected add-on

This profile charges a flat fee per unit ordered. For example, if you set a $3 per-item fee for US backers and someone orders 10 of that item, they'll pay $30 in shipping.

Per-item profiles are very easy to set up but are often less accurate compared to actual shipping costs. You can assign different per-item fees to each add-on or apply the same fee across multiple add-ons.

When to use Per-item Shipping:

• The item ships separately (e.g. large artwork, posters, items from a different warehouse)
• You don’t know item weights/dimensions
• You have thin profit margins and need to cover risks like lost packages

Quantity-Based Shipping Profile

Scalable fee applies to selected add-ons

This profile lets you assign shipping fees based on quantity ranges. For example, 1–2 items ship for $5, 3–5 for $7, etc. You can apply one profile across multiple add-ons. Ultimately, this allows you the most flexibility with your add-ons, as you can set pre-defined ranges, scale down costs as order sizes go up, and even do more custom profiles - such as a one-time base charge for all add-ons.  

It’s great for scaling costs, offering flat-rate shipping, or creating custom pricing rules like a one-time base fee. It strikes a good balance between accuracy and setup effort, but it's smart to slightly increase fees to cover future cost changes or fulfillment errors.

When to use Quantity-based Shipping:

• You don’t have exact weights, but items can ship together.
• You want to offer free shipping after a certain number of add-ons.
• You prefer a flat, one-time shipping fee across all add-ons.

Weight-Based Shipping Profile

Scalable fee applies to selected add-ons (must set up weights for SKUs)

This profile calculates shipping costs based on the total weight of add-ons. You can assign weights to each add-on SKU, and the system will total them to determine the shipping fee. This does not include pledge-level SKUs, which have separate shipping costs (often imported from Kickstarter or Indiegogo).

You’ll need relatively accurate info on item weights, dimensions, and shipping rates. While more involved to set up, this method gives backers the most accurate shipping costs. However, it’s a bit more rigid—each SKU can only have one weight value.

When to use Weight-based Shipping:

• You want to offer the most accurate shipping costs.
• You know your item weights and dimensions.
• All rewards will be fulfilled together.
• You already charged shipping for pledges.