At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What Is a Complementary Product?

Osmand Vitez
Osmand Vitez

A complementary product — more commonly referred to as a complementary good in economics — is an item that often has an interrelated use with another good. Economists typically use classic examples to define a complementary product, such as hot dogs and hot dog buns, automotive vehicles and rubber tires, or hamburgers and hamburger buns. The demand for one of these goods often drives the demand for the other due to their interrelated use. The purpose of defining goods as complementary can help economists understand the decisions made by homo economicus, the economic man. Companies can also use this information for general business purposes.

Supply and demand is the common way economists determine how an economy allocates resources. Price is the single greatest factor here as sellers and buyers attempt to reach a point at which they can maximize the movement of goods. Companies selling a complementary product have to ensure enough supply exists for each good. The price for each good tends to have separate equilibrium points as defined by supply and demand. Companies need to ensure the equilibrium for each good is close to each other in order to maximize the sales of each item.

Hot dogs and hot dog buns are complementary products.
Hot dogs and hot dog buns are complementary products.

When a price increase of one complementary product rises to high, consumers tend to look for a substitute good. This means consumers find an alternate good that offers similar value as the preferred good. The other item that sells well with the complementary product will also begin to falter in sales. Therefore, companies must find a way to unload complementary goods that will go unsold due to the price increase of the other product. Failure to do so will result in lost sales and obsolete inventory at some point in the future.

Condiments may be sold as being a great compliment to a hamburger.
Condiments may be sold as being a great compliment to a hamburger.

Companies may not be able to sell all complementary products on their own volition. For example, a hot dog manufacturer often focuses solely on selling hot dogs as this is the goal and purpose of the business. Selling hot dog buns, therefore, falls to another company, most likely a bakery. When the price of hot dogs increases exponentially — throwing the supply and demand equilibrium out of kilter — then the sale of hot dog buns will most likely fall. In this case, two companies will suffer faltering sales and must find ways to survive an economic downturn.

In some cases, a complementary product may sell better during economic downturns. For example, a decrease in purchasing power can result in consumers being unable to purchase filet mignon. Hot dogs then become the substitute good due to the lower prices of these items compared to filet mignon. As hot dog sales increase, so will the sales of complementary products, such as hot dog buns.

Discussion Comments


I think if I made a complementary product, I'd live in constant fear of the other product becoming unpopular or prohibitively expensive to consumers. I'll bet when people started wondering about the safety of hot dogs, the hot dog bun manufacturers got a little nervous. If people stopped eating hot dogs because of health concerns, then what would be a suitable and popular replacement? I'm sure companies that made ashtrays went through that thought process when cigarettes suddenly became less popular.


One thing I've noticed at grocery stores is that if the price of one product drops (like breakfast cereal), the price of a complementary product (like milk), will often go up. I've seen it happen with lunch meat and bread, or potato chips and dip. Sometimes I'll just go ahead and buy the more expensive complementary product, since I really can't enjoy one without the other. Other times I'll look for a cheaper alternative, like tortillas instead of hot dog buns.

Post your comments
Forgot password?
    • Hot dogs and hot dog buns are complementary products.
      By: Brenda Carson
      Hot dogs and hot dog buns are complementary products.
    • Condiments may be sold as being a great compliment to a hamburger.
      By: Matthew Antonino
      Condiments may be sold as being a great compliment to a hamburger.