Emergency Fund vs Credit Card: When to Use Which

A surprise bill lands and you've got two options: drain the fund or tap the card. The right choice turns on your card's APR, your savings rate, your utilisation and the size of the hit. This runs your exact numbers through a decision framework so you pick the cheaper, smarter path instead of the one that feels less painful in the moment.

I faced an unexpected expense of {EXPENSE_AMOUNT} for {EXPENSE_TYPE} and I'm not sure whether to use my emergency fund or put it on my credit card. My emergency fund balance is {FUND_BALANCE}, my credit card APR is {CREDIT_APR}%, my current credit utilisation is {CREDIT_UTILISATION}%, and my fund earns {SAVINGS_RATE}% interest. Walk me through a decision framework for this exact scenario covering: (1) the true cost of each option over {REPAYMENT_MONTHS} months, (2) impact on credit score, (3) impact on financial resilience, and (4) a clear recommendation. Then give me a general rule of thumb I can use for future decisions like this.