> ## Documentation Index
> Fetch the complete documentation index at: https://docs.stockful.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Cost adjustments

> Add a cost to stock you already hold, such as freight billed after the stock arrived, and fold it into each product's average cost.

A **cost adjustment** adds a cost to stock you already hold, without changing how many units you have. Use one for a cost that arrives after the stock did:

* **Onward freight** from a holding warehouse to the locations you sell from, billed when the stock moves
* **A late invoice** for freight, duty or fees on a purchase order you have already received

Stockful folds the cost into each product's [average cost](/user-guide/purchasing/purchase-orders/costs#cost-history-and-average-cost), so your margins include it. A purchase order's own [adjustments](/user-guide/purchasing/purchase-orders/costs#how-adjustments-are-spread) lock once stock is received, so a cost that turns up later is added this way.

## Adding a cost

Open **Counts & adjustments** from the **Inventory** page, then **Cost adjustments**, and click **Add cost**. From a purchase order that has received stock, you can also choose **More actions** > **Add a late cost** to start with the products it received.

1. **Add the products the cost belongs to.** Search for products, or use **Load from purchase order** or **Load from transfer** to bring in everything that order received or that transfer moved. Loading one replaces the products already on the form.
2. **Check the units.** A product's units decide its share of the cost. A purchase order or transfer brings the units it received or moved. A product you add yourself starts with everything you hold, which spreads the cost evenly over every unit.
3. **Enter the cost.** Choose a type, enter the amount, and put the invoice number in **Reference**. A negative amount is a credit.
4. **Choose how to split it.** By **Value**, more expensive products take a bigger share. By **Quantity**, every unit takes the same share.
5. **Save.** Stockful asks you to confirm, because a cost adjustment can't be changed afterwards.

As you type, each line shows its current cost, its share of the amount and its new cost.

## How the new cost is worked out

Each product's share is spread across everything you hold of it, in every location Stockful tracks. It is the same sum you would do by hand: the current cost, plus the share divided by the units on hand.

For example, £300 of freight covers 100 lanterns and 50 throws. The lanterns cost £10.00 and you hold 400. The throws cost £20.00 and you hold 200.

| Split by | Lanterns                             | Throws                               |
| -------- | ------------------------------------ | ------------------------------------ |
| Value    | £150 share, so £10.00 becomes £10.38 | £150 share, so £20.00 becomes £20.75 |
| Quantity | £200 share, so £10.00 becomes £10.50 | £100 share, so £20.00 becomes £20.50 |

The shares always add up to exactly the amount. The new cost is kept to two decimal places, like every cost in Stockful.

If a product has no average cost yet, because nothing has been received against a purchase order, Stockful starts from its cost per item in Shopify.

## What stops a line

Stockful won't save while a line has a problem, and marks the line with it:

* **Nothing on hand** - there is no stock to add the cost to. Remove the line.
* **No cost** - the product has neither an average cost nor a cost per item in Shopify. Set a cost per item first.
* **Below zero** - a credit would take the cost below zero.

## Correcting a mistake

A saved cost adjustment is permanent. Stock is sold and received after it is saved, so it can't simply be reversed. To correct one, add another cost adjustment for a negative amount against the same products.

## Syncing to Shopify

If **Sync landed cost to Shopify** is on in [Purchasing settings](/user-guide/purchasing/settings), saving a cost adjustment also writes each product's new average cost to its **cost per item** in Shopify, the same as a receipt does. If you keep cost per item up to date another way, leave the setting off and Stockful won't change it.

## Where it shows up

* **Cost adjustments** lists every one with its type, reference, source and amount. Open one to see each product's cost before and after.
* A **purchase order's timeline** records a late cost added from it, with a link to the cost adjustment.
* The **Cost history** report includes cost adjustments, with **Source** telling them apart from receipts and edits made in Shopify.