Can I exchange iPhone 16 purchased at Costco at an Apple Store?

Exchanging an iPhone 16

Here is the Returns and Exchange policy from Apple's website. But unfortunately you wouldn't be able to do that. You'd have to return it to Costco and then purchase a new one through Apple.

Standard Return Policy

There are a few important things to keep in mind when returning a product you purchased online from Apple:

• You have 14 calendar days to return an item from the date you received it.
• Only items that have been purchased directly from Apple, either online or at an Apple Retail Store, can be returned to Apple. Apple products purchased through other retailers must be returned in accordance with their respective returns and refunds policy.

Apple’s return policy does not apply to anything purchased from another retailer.

just wanna ask if I can change my iphone for purple color from Apple store?

No, you would have to do this through Costco.....if they will allow it.