> Documentation index: [Saleor](/llms.txt) · [This section](/developer/llms.txt)
> Source: https://docs.saleor.io/developer/discounts/displaying-catalogue-discounts

# Displaying Catalogue Discount Prices

Saleor API provides pricing information that can be consumed by your storefront for four different scenarios:

-   Individual `ProductVariant` pricing, which provides prices of a specific SKU (`VariantPricingInfo`)
-   Aggregated `Product` pricing, which provides a range of `ProductVariant` prices (`ProductPricingInfo`)
-   Pricing information included in `CheckoutLine` for products that are added to the cart/checkout
-   `OrderLine` pricing information concerning products that were purchased by the customer

note

Only [catalogue promotions](/developer/discounts/promotions.md) will result in changes to Product/Variant pricing. Order discounts and vouchers are applied only after the product is added to the Checkout.

<a id="types-of-promotional-prices"></a>

### Types of Promotional Prices

There are three main types of promotional prices that you can use to display prices in a storefront:

-   `price` - includes relevant discounts (depending on context)
-   `priceUndiscounted` - price before any discounts are applied
-   `pricePrior` - price in the period before the promotion. This price is not tracked automatically by Saleor (see section below)

On top of that, Saleor provides discount calculations relative to `priceUndiscounted` and `pricePrior` for `Product` and `ProductVariant`.

<a id="using-priceprior-as-a-base-for-discount-calculations"></a>

### Using `pricePrior` as a Base for Discount Calculations

info

`pricePrior` is available starting from **Saleor 3.21**.

For some geographies, it might be required to calculate discounts based on the lowest price before the promotion. An example of such a requirement is the EU Omnibus directive. Given that there are many different interpretations of the "lowest price", Saleor does not track `pricePrior` automatically. However, it can be provided using [`productVariantChannelListingUpdate`](/api-reference/products/mutations/product-variant-channel-listing-update.md) or [`productVariantBulkUpdate`](/api-reference/products/mutations/product-variant-bulk-update.md) mutations.

After providing `pricePrior` to `ProductVariantChannelListing`, it will be propagated to pricing information for `Product`, `ProductVariant`, and `CheckoutLine` as mentioned above.

<a id="example-workflow-using-a-custom-saleor-app"></a>

#### Example Workflow Using a Custom Saleor App

To implement the EU Omnibus directive, you can use a custom Saleor Application that:

-   Tracks changes in `ProductVariant` prices using webhooks (`PRODUCT_VARIANT_UPDATED`) or/and queries and records them in a database
-   Monitors when a promotion starts using webhooks (`PROMOTION_STARTED`) and obtains a list of relevant `ProductVariants` from the catalog predicate
-   Calculates the price prior to the promotion (taking into account custom requirements) and updates `pricePrior` using [`productVariantChannelListingUpdate`](/api-reference/products/mutations/product-variant-channel-listing-update.md) or [`productVariantBulkUpdate`](/api-reference/products/mutations/product-variant-bulk-update.md) mutations.