Michael Finney helps you save online with coupon codes

SAN FRANCISCO (KGO) -- A new study out shows when shopping online, less than one-third of people regularly use a coupon code. That's money your family could use.

You've seen the boxes on the checkout page of shopping sites. Sometimes they are welcomed, sometimes, not.

"So you are shopping on line you think you are getting a great deal," Consumer Action's Joe Ridout said. "You are psyched at the price you are paying for what you are getting and then you get to the checkout screen and see a box asking for your code. Suddenly this reframes the whole experience."

We have all been there. The good feeling of a great deal goes bad because of a little tiny box.

"It can be a very frustrating experience to arrive at a check out window and then not have a code and think how much more could I have saved? Is this code 50 percent off? It is setting people up for disappointment," Ridout said.

And we see those boxes everywhere.

"When you see one of those boxes you should search for a code, because if you are not you are not filling it in you are leaving money on the table," Regina Novickis said.

Novickis is a savings expert for promotionalcodes.com. She says if you don't have a code, search for one, or better yet, look for codes before you see a box.

"Before you even start your shopping go to a site and check out what promotion codes are available and then start your shopping," she said. "Very often you can compare those products, prices and services online and find something less expensive if you are not committed to a specific brand."

If there isn't a code available now, she says wait till the next three day weekend and there is a good chance there will be one then.

Online retailers like to offer coupon codes over long weekends.

"If you have a merchant that you are shopping from frequently, follow them on social media," Novickis said. "That is a really good place to find some additional exclusives and offers you would not find elsewhere. Food brands in particular, places like Panda Express and Starbucks will very often provide exclusives for new products that they are launching via their soc8ial media channels and you can find those codes there."

And here's a tip no one else will tell you: you can use coupon codes in stores. They usually have to call a manager over, but then they punch it into the cash register and voila!