Customer is who purchase the product, consumer is the end-user, the actual person or entity that will use it.

If you buy, for example, a Samsung TV from Walmart. Walmart is Samsung's customer, but they are not the consumer. Walmart, in some fashion, is paying Samsung for that TV and reselling it to you. You are the consumer of that TV and a customer of both Samsung and Walmart.

Hypothetically if you're gifted a Samsung TV and spent no money on it yourself, you are technically a samsung consumer, but not a customer.

In common usage, the terms are often going to be used as synonyms, if you have a problem with your TV you're going to call Samsung customer service, whether or not you actually are technically a customer.

In addition to all the answers here, a costumer is someone who creates and/or sells costumes. The term is often used as a synonym for customer by people who don't type/spell well.

Customers pay; consumers use. Sometimes they're the same, often they are not.

Ad-supported services: If you search for something on Google, you are a consumer. Google's customers are the companies paying for sponsored links at the top of your search results.

Kids toys (and other gifts): The kid in the sandbox playing with a Tonka truck is the consumer of the product but their parents (grandparents, etc.) are the customers.

"Enterprise" solutions: Corporate IT departments are usually the customer, though they may never use the product. Other employees are the consumer, but they had no choice in buying it so they're not the customer.

If you are a producer of doohickeys and I buy them from you to sell on, then I am a retailer and a customer of yours, but I do not actually consume the doohickeys. It is my customers who are the consumers.

Or, if you produce a certain show and I pirate that show from a torrent site and watch it, then I am a consumer of that show - but not a customer.

Customer is someone looking for a product, a consumer is a repeating customer.

As others have said, there can be a difference.

Another example is children, my kids are consumers but almost never customers. I as the parent am the customer in most transactions for goods/services they consume. They sometimes buy candy or toys with birthday money, they would be both customer and consumer for those.

Consumer is an entity that uses- “consumes”- products; as compared to an entity that produces products for consumers.

Customer is much more specific- they’re more relative to the company in question; a farmer is a producer- they grow the food. Their customers are the people at the market (individuals, presumably , and these are consumers) and the grocery stores, even if those stores themselves aren’t the actual consumers. For that, their customers are the consumers,

And the farmer is presumably a customer of a farm supply store (and the tractor people, and stuff,)

Imagine the flow of goods as a tree: the suppliers of raw materials are the base, manufacturers are the main branches, wholesalers and distributors are the smaller branches, retailers are the twigs, and consumers are the leaves at the end.

Every node is a customer of the previous node, but only the last customers are consumers.

Yeah technically but the words are interchangeable and it's only management types with pointless jobs that are going to be first up against the wall who send out emails about the requirement to call people consumer, customer, etc.

The difference is the relationship. A business has customers. The economy has consumers.

It depends on context whether or not the terms are interchangeable. A customer is generally the party who buys something in an individual transaction, while a consumer is more like the economic force that creates demand for a thing to be bought and sold.

In capitalism people are called consumers. This is the working class, people who make up society. Families and communities. But to capitalists we are consumers. Capitalism doesn't meet the needs of people, it exploits people for profit. Looking at people as "consumers" is not a great way to see people.

It depends also on what type of business. For example in Finance a consumer is a real person who buys/borrows uses something but a customer is a general term for a person, business, organisation or partnership that buys goods or services.

For example, I might have an account at XYZ Bank and so might a company. We are both customers of XYZ Bank but I am a consumer and the company isn’t.

[to complicate things small businesses might class as consumers in some jurisdictions]

consumer seems much more vague and less... transaction-y...

Customer is specific, consumer is more general.

Example = That customer wanted oat milk, but consumers in general haven't taken to oat milk.

They are synonyms the way 'aroma,' 'odor,' and 'smell' all mean the same thing but are used differently

They're synonymous. They both mean a person or business that buys goods or services. A better way to go about it is to consider the prose. What sounds better given the context.