> ## Documentation Index
> Fetch the complete documentation index at: https://shipmagic-docs.speedysquirrelhq.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Incremental / Per Item Rates
> Charge a base price plus an additional amount for every unit
An **Incremental** rate charges a base price, then adds more for every N units beyond a starting point. It's the natural shape for "\$5 for the first item, \$2 for each additional one".
## Setting one up
Set **Calculation parameter** to **Number of items**, **Total weight of items**, or **Total price of items** — whatever the increment should be measured in.
Four fields appear.
| Field | Meaning |
| - | - |
| **Base price** | The starting charge, applied once. |
| **Incremental price** | Added for each step beyond the start. |
| **Per each** | The size of one step. |
| **Start from** | Where incrementing begins. Leave empty for the default. |
## How the fields combine
The rate is:
```text theme={null}
Base price + (Incremental price × steps beyond "Start from")
```
where a step is **Per each** units.
With Base price `5`, Incremental price `2`, Per each `1`:
| Items in cart | Price |
| - | - |
| 1 | 5.00 |
| 2 | 7.00 |
| 3 | 9.00 |
| 5 | 13.00 |
Setting **Per each** to `2` would instead add \$2 for every *two* extra items.
## Weight-based increments
The same structure works for weight. With **Total weight of items** as the calculation parameter, Base price `10`, Incremental price `1.50`, Per each `1`, and Start from `5`, a 5kg parcel costs \$10 and each kilo above 5 adds \$1.50.
**Per each** is expressed in your store's weight unit, shown as a suffix on the field.
## Incremental vs. Ranged
Both produce a rising price, but they behave differently between steps:
* **Incremental** is smooth and unbounded — it keeps climbing with no ceiling.
* [**Ranged**](/ranged-rates) is a lookup table — one flat price per band.
Choose Incremental when cost genuinely tracks quantity. Choose Ranged when you have negotiated carrier prices for specific brackets.
An incremental rate has no upper limit by default. On a very large order it can produce a surprising number — set a ceiling with [Setting Maximum and Minimum Shipping Rates](/setting-maximum-and-minimum-shipping-rates).
## Range + Incremental
To apply an incremental charge only inside a particular band, use the **Range + Incremental** rate type. You give a Range Start and Range End first, then the base and incremental fields. Outside the band, the rate does not apply.
## Examples
**\$5 first item, \$2 each additional**
```text theme={null}
Rate name: Standard Shipping
Calculation parameter: Number of items
Rate Type: Incremental
Base price: 5
Incremental price: 2
Per each: 1
Start from: 1
```
**Free up to 3 items, then \$1.50 each**
```text theme={null}
Calculation parameter: Number of items
Rate Type: Incremental
Base price: 0
Incremental price: 1.50
Per each: 1
Start from: 3
```
## Related
Flat price per band instead of a smooth climb.
The per-product use case, start to finish.
Cap an incremental rate.
The full rate dialog reference.
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