Close to one out of five U.S. Internet users will go online to buy gifts for Mother’s Day according to a survey by BIGresearch for the National Retail Federation called “2008 Mother’s Day Consumer Intentions and Actions Survey.”

“Consumers will be very cautious with their wallets this Mother’s Day, heeding mom’s advice that she really doesn’t need much,” said BIGresearch Vice President of Strategy Phil Rist. “Gas prices and other economic issues will still be at the forefront of people’s minds as they shop around for the perfect gift for mom.”

Those surveyed said they planned to spend an average of $138.63 for Mother’s Day this, down slightly from $139.14 last year. The NRF said it expected total consumer spending for the holiday to reach $15.8 billion.

A small portion of U.S. adults will be going online for more than just shopping. Five percent said they planned to contact their mom online on Mother’s Day.