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

# Price adjustments

Price adjustments let you modify the prices on a plan on a per-customer basis. For example, you might use the same plan for all your enterprise customers but use price adjustments to give each customer an individually negotiated discount.

Another common use case for price adjustments is "cost-plus" pricing. In this model, your base plan has prices reflecting your business's underlying costs, and you use price adjustments to apply a percentage-based markup.

## Adjustment types

Price adjustments are modeled as:

* **Percentage-based** increases or decreases. For example, offer a 15% discount or add a 15% markup for a customer.
* **Fixed amount** increases or decreases. This is used to modify a price by a specific amount, for example, decreasing the price of a gigabyte of data by \$0.50.
* **Price override**, which sets a specific price for an invoice charge. For example, you can set the price for a gigabyte of data to \$0.35 for a single customer.
* **Quantity override**, which lets you set a specific quantity for a fixed charge. For example, an underlying plan may default to 1 developer license (a fixed charge). You can use a quantity override to set the number of licenses for a specific customer to 10.

Invoices show the adjusted prices without the details of how they were computed. For example, if a gigabyte of data costs $1 in the plan and you apply a 15% decrease adjustment for a customer, that customer sees a unit price of $0.85 on the invoice with no mention of the 15% adjustment.

### Composite charges

You can also modify the value of a composite charge on a per-customer basis using price adjustments.

The quantity on a composite charge can be used to enable or disable the charge. To enable a composite charge for a subset of customers on a plan, set the quantity to 0 during plan creation, then apply a quantity override during plan assignment to set the quantity to 1.

## Apply price adjustments with the API

Pass price adjustments in the `price_adjustments` array when you [add a plan to a customer](https://docs.staging.metronome.com/api-reference/plans/add-a-plan-to-a-customer.md). Each adjustment targets one charge on the plan:

| Field | Description |
| - | - |
| `charge_id` | Required. The ID of the plan charge to adjust. Use [list plan charges](https://docs.staging.metronome.com/api-reference/plans/list-plan-charges.md) to list a plan's charges. |
| `adjustment_type` | Required. One of `percentage`, `fixed`, `override`, or `quantity`. |
| `value` | The amount of change to the price. Percentage and fixed adjustments can be positive or negative. Express percentages as decimals, for example `-0.05` for a 5% discount. |
| `quantity` | The overridden quantity for a fixed charge. Use with `quantity` adjustments. |
| `tier` | For tiered pricing, the metric value at which the tier's price applies. |
| `start_period` | Required. For price ramps, the number of billing periods that pass before the adjustment applies. |

```json theme={null}
{
  "plan_id": "d2c06dae-9549-4d7d-bc04-b78dd3d241b8",
  "starting_on": "2026-01-01T00:00:00.000Z",
  "price_adjustments": [
    {
      "charge_id": "644a6f1f-6cbb-4bd6-a3b9-21e2e7aa4f28",
      "adjustment_type": "percentage",
      "value": -0.15,
      "start_period": 0
    }
  ]
}
```

To review the adjustments applied to a customer's plan, use [get the plan adjustments for a customer](https://docs.staging.metronome.com/api-reference/plans/get-the-plan-adjustments-for-a-customer.md).