Sale prices for single products, also called single product discounts, are managed by a product owner. They can be configured on a product details page in the store's Admin area.
A sale price set for a single product overrides all other possible group discounts that may apply to this product.
To set a sale price for a single product:
1. Select a product on a product listing page (Catalog -> Products) in your store Admin area and open the product details page for editing.
2. Scroll down the page and locate the ‘Prices & Inventory’ section.
Here you need to enable the “Sale” checkbox for the sale price setting fields to become visible:
3. Set a sale price either in absolute value or in percentages:
The sale price defined for a product will also apply to all product variants (if any) in case no special sale price is configured for them.
A sale price can also apply to wholesale prices if a discount is set in percentages. More details on applying discounts on wholesale prices see in Wholesale Pricing to Sale Offers.
4. Click Update product to save changes.
Products with a sale price enabled are marked with a ‘Sale’ tag on the product listing pages in the store's Admin area.
Please do mind that the product listing pages in the store Admin area display the default product price. The discount values applied to a product can be checked on the product details pages only.
As for the storefront, all discounted products are marked with a special "% OFF" discount label on the listing and a product details page. The product details page also shows the original (default) product price.
Product listing page
Product details page