Should I use my emergency fund to pay off a high-interest credit card?

Partially, with a safety net. Guaranteed 22%-plus interest on a card usually beats the interest you'd earn keeping every dollar in savings, so it's tempting to drain the fund. But wiping out your emergency fund entirely is risky: if a real emergency hits, you'll just run the card back up, often at a higher balance.

A balanced approach is to keep a small buffer, such as one month of expenses or a $1,000 to $2,000 starter cushion, and throw the rest at the card. Your available credit then acts as a backstop of last resort while you rebuild the fund. If your income is unstable, keep a bigger buffer. The goal is to attack the expensive debt without leaving yourself one flat tire away from more of it.