Usually, they just scan entire cash drawers at the end of the day. But, if they have concerns about an individual deposit, they will scan it in real time. If they have a large withdrawal, they usually pay it out with banded pre-scanned bills.
I assume all those serial numbers and bank locations go into a central US Treasury data base each day, although I do not know that for a fact.
It is not a big job - it takes longer to stack and unstack the bills than it does to scan them.
Moving from paper serial numbers to electronic serial numbers does not seem like an especially big change to me.
Unless someone lives completely off the grid, the US Treasury already has a pretty good idea where your money comes from, and where you spend it.
I’m not so sure they do. Unless you opt for bigger bills maybe.
Consider I pull a 20 out of the ATM. I spend it at Walmart. Some other guy buys something small with a 50. He gets the 20, keeps it in his wallet for a week then goes and buys a burrito with it.
It finally makes its way back to the bank to be scanned in. There is a lot of data missing, and the treasury has no idea what happened in the middle.
I guess with big transactions they would know more, like if I took out $5k then bought a car from some dude with it. Assuming he turned around and put it all right back in the bank.
But if he kept it and used it for WAM for a year...
Probably the only useful data they would have from scanning bills that is if they found a pile of cash and all the SNs were distributed to one person, they could go talk to that guy.
You got a link for that info