Some states have a minimum cash on hand requirement - NV has a formulation on a spreadsheet that you can find on the GCB website. Some states require that there is back up holding to pay off all slot machine jackpots. Some states don't require anything at all.

The state that I am in does not have a requirement for the cage to hold a certain amount of cash. To free up cash flow for the corporate treasury the past few years we use a cash load formulation that helps us reduce our cash on hand. In fact the cash load number is one of the targets we have to hit to be eligible for bonus, so we watch cash load like a hawk. No we have never ran out of money to pay off guests, we have been low on money if we have an unexpected spike in business, we have a few tricks up our sleeves to have enough money to keep the casino running.

Basically we watch cash load like we watch labor, we go by planning and analysis reports and marketing plans to determine our business levels and how they effect the casino and then we put out a directive on how much cash to hold for business levels. If we have big events that will spike our cash usage and we determine that we cannot hold enough cash from the Slot and Table drops then we will order money from the bank. Events like New Years Eve, Major Slot Tournaments, or WSOP circuit events can spike our cash usage.