Anyone who is interested in establishing or rebuilding their credit can apply for the Indigo Mastercard. To be pre-qualified or approved, you must: Must be at least 18 years old (19 in AL), have a valid social security number, physical address, and a US IP address. Not have had an Indigo Mastercard Account that charged off due to delinquency. Meet additional credit qualification criteria, including a review of your income and your debt, and identity verification requirements.