우측 상단 - 계정 - Wallet 눌러보시면 유효기한 나와요.

Do Wallet Funds expire?

Certain types of Wallet credit will expire after 6 months of Wallet inactivity. Those types include Humble Rewards from Store purchases, promotional credit from bundles, and any other forms of credit that indicate expiry in the terms. Any activity in your Humble Wallet, like reloading funds, using credit towards a purchase, or getting more promo credit, will refresh your expiration date for 6 more months. Wallet funds that you’ve reloaded and paid for yourself will never expire.

Your Humble Wallet page will display your current balance for both types of credit, if applicable, including the current expiration date for any credit that expires.

If you have both expiring and non-expiring credit when you make a purchase, payment will automatically pull from your expiring credit first (and that will refresh your expiration date for 6 more months, too).

Note: Credit of any type earned before May 30, 2018 will not expire

위 문구에 나와있는거 처럼 월렛 중 [Wallet Funds]는 유효기간이 없고, [Expiring Wallet Credit]는 유효기간이 있습니다. [Expiring Wallet Credit]에 돈이 있는 경우 유효기간이 별도 표시되는 것으로 알고 있습니다.