Now police want to make sure everyone is double-checking their cash register and their wallets.
"A lot of times we don't even know who they are they come here for a day they spend a lot of money and they move on to the next place," Says Detective John Clark of the Abilene Police Department.
As holiday shoppers take to the stores, counterfeit money makers hit the printers for those strapped for cash.
"Generally this time of year we do get an increase in financial type crimes and it is because of the Christmas season," Said Clark.
And this year is no different.
The Abilene police department saw a handful of cases just last week.
One of them, involving a Compass Bank, where someone cashed 3 forged checks for a total of $10,000. The case is still under investigation, but police say it's time to start double checking everything.
"The easiest way to do this is to mark your bills with a marking pen," Said Clark.
While marking pens are 90 percent effective, they will give a false positive on a bill from 1985 or older.
There are also other easy ways to spot counterfeit cash. Like feeling the texture of the bill and checking for ink runs. But, police say they need your help to keep these cases to a minimum.
"Understand that this is the time of year, we have had several recent cases where counterfeit money is being passed, enough to lead me to believe that there's probably someone here locally that's manufacturing that money," Says Clark.
Forgery is a third degree felony in the state of Texas but also carries a federal offense.
Receiving a fake bill as change does happen, and police say if you do come across a bill you believe to be fake, call them immediately.
"People have legitimately come into contact with possession of a counterfeit bill without knowing it, and then try to pass it later, well we're not just going to swoop in and put you in jail because you're trying to pass a counterfeit bill, we're going to try and find out where it came from."