Yes, affiliate sales can be incremental. Affiliate sales can help to increase overall sales and revenue for a business, as they provide an additional source of income. Affiliate sales can also help to increase brand awareness and reach new customers.
Incremental sales refer to units sold through a specific marketing campaign. These campaigns can be in the form of affiliate marketing, but also influencer, social, media ads and other channels.
For it to be an incremental sale, someone outside the company (not the company itself) has to drive the lead that results in that purchase. That sale could not have been made without the push from that partner, affiliate, or social media channel.