Like most Americans, you probably have a long-unused gift card lying somewhere, half-forgotten. In fact, more than half of Americans have unused gift cards totaling an average of $116 per person, according to a 2021 survey by personal finance website Bankrate.

If you need a reason to finally spend it, consider rising inflation, which has reduced your gift card's value by roughly 13% since 2019, according to CNBC calculations using data from the U.S. Bureau of Labor Statistics' consumer price index (CPI).

A $100 gift card issued in May 2019 would only retain $87.61 of its spending power if redeemed in May 2022, the month with the most recent CPI data.

However, it's worth noting that some items have been more affected by inflation than others. The 13% difference is based on a weighted average of the CPI index as a whole, so price changes on individual items will vary. For instance, as of May, dishware prices had risen by 6.1% over the last year, while men's suits and coats had risen 22.3% in that same time. 

But with year-over-year inflation up 8.6% since last June, one thing is clear: Inflation is eating away at your gift card's spending power, and will continue to do so until you use what's left. Retailers will likely continue to raise prices in the meantime. 

Another reason to redeem unused gift cards: some may expire or have inactivity fees that kick in after 12 months of non-use.

Rules for gift card expiry and inactivity fees vary by state. To learn more about the rules in your state, the National Conference of State Legislatures has a helpful search tool.

How to get rid of your gift cards

The first step in using up your gift cards is knowing what you have. With most cards, you can verify the remaining balance using either a toll-free phone number or website printed on the card. 

To keep track of the verified balances, write them out on the face of each card using a black marker. Then, it's just a matter of shopping, either in-store or online, depending on the retailer.

However, it's not always easy to spend gift cards at retailers that don't offer anything you want to buy. In that case, you can try selling your gift cards on reseller sites like CardCash.com or ClipKard.com. 

Keep in mind you won't be able to sell these cards for their full value. Sought-after cards like Walmart can be sold for up to 90% of their value, while more niche cards, like a Subway restaurant gift card, will be sold for closer to 60% of their value. It might not be worth selling unless you won't use the card and could use the cash.

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