Refill prices start at $3 for 100MB and vary based on the chosen eSIM data bundle. You may check the available eSIM data bundles and refill prices* for each of them at https://myaccount.simfinity.ai/
*Please mind that you can use the entire package of the data plan you choose, until the last MB. The balance of your eSIM remains valid for a lifetime (if refilled at least once per year).