Employees who hit 25 years at Costco can get a sheet cake with the Costco logo on it.

"The cake thing is really rare because it's not every day an employee hits 25 years with the company," said the cashier assistant who is about to hit two years with a Costco in California.

"They'll congratulate the manager who spent 25 years amongst your peers in the meeting," said another Costco employee who has been with the company for 22 years. "They'll put the cake in the break room and that way all the employees know that you've reached your 25 years and they get to share in the cake."

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Seven Costco employees in places including California, New Jersey, Minnesota, Ontario, and Ohio mentioned that they had heard of the cake in varying forms for an employee who hits 25 years with the company.

A few employees mentioned that the perk depends on the warehouse and the manager, and it's not clear if the cake is a store policy or a tradition some stores have adopted.

A representative for Costco declined to comment for this story.

"At ours, there wouldn't be a 'free' cake for the employee," said a Costco worker in Ohio. "There would be cake for everyone — multiple cakes — in the break room celebrating the milestone."

The Costco cake with a logo on it is so special, that stores exclusively reserve it for employees, and the average customer is usually not allowed to get a cake with a Costco logo.