Ensure "InstaCredit" is enabled in your in-app menu.
Click the button located next to your current credit balance. Follow the prompts to purchase single or multiple credits. InstaCredit (Mobile App) :
Select the book you want and follow the pop-up prompts to complete the transaction.
If you frequently need more credits, it may be more cost-effective to upgrade your monthly plan:
: Unused credits from your monthly plan roll over to the next month, though there may be limits on the total number you can store. Audible | Listen to Audiobooks, Podcasts, & Originals
: You must have a paid subscription to purchase and use credits.
: While you can purchase gift subscriptions for 1 to 12 months, you cannot buy a specific single credit to gift to another person's existing account.
This feature allows you to buy a credit and apply it to a book instantly without leaving the app.