Amazon is having its third annual Prime Day, and the sales don't stop there.

Things kicked off at 9 p.m. Monday night and the major savings are set to continue until 3 a.m. Wednesday.

If you shop Amazon Prime, you'll see the lightning deals that offer a discount for a limited time for Prime members only.

So far, Amazon Prime has some pretty good discounts. Amazon says it has millions of shoppers and its top item is the Amazon Echo, which is listed at $89.99, a 50-percent saving.

But before you go flocking to Amazon, be sure to check prices on other websites as well.

Macy's, Best Buy, JCPenny, and Khol's also have some big online sales and free shipping going on all day.