While a few thousand Californians are still waiting to receive the Middle Class Tax Refund, more than a million debit cards preloaded with hundreds of dollars are sitting unused, according to state data.

The state started issuing the direct payments, between $200 to $1,050, last October to help combat the rising cost of living. The “inflation relief” payments were sent out two ways: direct deposit and debit card.

Of the 9.6 million debit cards sent out, 87% have been activated, according to the California Franchise Tax Board (FTB).

That leaves 13% of cards that haven’t yet been activated or used – about 1,248,000 people who qualified for the assistance, but haven’t cashed in yet.

The unactivated cards hold an estimated total of $600 million in unused benefits.

The FTB is sending out letters to people who haven’t yet activated their cards, reminding them to do so. Once a card is activated, it can be used to make purchases in stores or online. People can also transfer the balance straight into their bank account if they prefer.

Even most of the people who have activated their cards haven’t spent all the money, the FTB reports. Only 45% of activated cards have a zero balance. The rest still have some money loaded onto them, though it’s not clear how much.

Meanwhile, the FTB is working to send about 5,000 more debit cards out by the end of the month. The agency expects this to be the last batch of new payments.