San Jose finalized the ordinance early last year and the warning signs had been up for months, but with 5,000 retailers impacted, there is a learning curve.
"It's a good idea; I think it's good that at least all the stores have to do it, and not just the grocery stores," shopper Mike Cox said.
San Jose's plastic bag ban is one of the strictest in the country. Only non-profits and restaurants are exempt, making reusable bags the must-have hot seller.
"It was only $1 for this bag and yes, I will use it again," shopper Ever Leon said.
There is always the option of paying 10 cents for a paper bag, but the new rules are giving "carry out" new meaning.
"I'll go to my place, get my bags and come back to my car and bag it myself," shopper Kevin Way said.
In the Willow Glen shopping district, some local business owners are setting themselves apart from the chains, offering to kick in the dime for awhile.
"We like to keep our customers happy and have them come back and have them feel like they are part of our family as much as the employees feel it," Domus employee Callie Douthit said.
Not to be outdone, other stores are rewarding shoppers for reusing.
"To encourage guests to use their reusable bags, for every transaction that a guest brings a reusable bag, they get 5 cents off," Target Executive Guest Leader Jay Patel said.
In the end, the plastic bag ban is not about the money, but the environment. The DeFanti family says there are no faux pas when it comes to bringing your own.
"Sometimes I feel a little weird going into another store with a different bag but it's doing more good, and I shouldn't feel uncomfortable because it's more important not to have the plastic bags," Adrienne DeFanti said.
For the next 12 months, a papaer bag in San Jose will cost 10 cents. Next year, the price will jump to 25 cents.