Amazon.com is expanding an internal policy of paying employees cash to leave their jobs if they're unhappy and not engaged in the company long term.

In an annual letter to shareholders Thursday, Amazon CEO Jess Bezos outlined details of the longstanding offer, under the header "Please Don't Take This Offer."

The idea is simple. Once a year, the company offers cash payouts to any employee who no longer wants to work for the company. The offers start at $2,000 for employees have worked for the company for at least a year and escalates to $5,000 after enough years of service. The innovative idea was first developed by Zappos, an online shoe retailer that Amazon absorbed five years ago.

"The goal is to encourage folks to take a moment and think about what they really want," Bezos said. "In the long run, an employee staying somewhere they don’t want to be isn’t healthy for the employee or the company.

"We hope they don’t take the offer; we want them to stay," Bezos said.

The company is in the midst of an aggressive expansion plan, adding thousands of new employees and adding dozens of new warehouse and distribution centres to handle the volume that comes with millions of new products.

Amazon had 117,300 employees at the end of 2013, an increase of about 30 per cent from the figure 12 months earlier.