Emergency Fund or Pay Off Debt?
If you have cash in the bank and debt at a high rate, the mathematically cheapest move is to pay the debt. But cash is what keeps a surprise bill from going back onto a card at 25%. The practical answer for most people is a middle path: keep at least one month of essential expenses, ideally three, and put the rest toward the highest-rate debt.
This calculator runs three scenarios on your numbers: keep all your cash, keep a set number of months of expenses and put the rest on debt, or put everything on debt. For each it shows the debt-free date and total interest, so you can see exactly what a buffer costs and decide how much safety you want to pay for.
Results
Our read
Keep $5,000, put $4,000 on debt
That keeps 2 months of expenses in reserve and still saves $1,601 in interest versus keeping everything in cash.
Avalanche saves you $250 versus snowball, but your first debt clears in 9 months instead of 1. If early wins keep you going, snowball costs $250 extra for that.
At minimum payments only, these debts take 4 years 10 months and cost $4,999 in interest. With $150 extra a month you are debt-free in 12 months after $528 in interest.
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Frequently asked questions
Should I build an emergency fund or pay off debt first?
Do a little of both, in this order: get one month of essential expenses in cash, then attack high-rate debt with everything else, then build the fund up to three to six months once the expensive debt is gone. The one-month buffer is what stops the next surprise from undoing your progress.
How big should my emergency fund be while paying off debt?
One month of essentials is the floor; two or three if your income is irregular or your job is uncertain. A full six months while carrying 25% card debt costs a lot in interest. Once the high-rate debt is gone, redirect the payment into the fund until it reaches your target.
Is paying off debt a good use of savings?
For high-rate debt, yes: paying a 24% card with cash earning 4% is a 20-point improvement, guaranteed. For low-rate debt like a 3% car loan it is close to a wash and the liquidity is worth more. The calculator quantifies the interest saved so you can weigh it against having the cash.
What if I use my emergency fund and then have an emergency?
That is the scenario the buffer prevents. If you have already used it, the fallback is the card you just paid down, which is why the tool warns when a scenario leaves you below one month of expenses. Rebuild the buffer before resuming extra debt payments.
Where should I keep my emergency fund?
Somewhere you can reach it within a day or two without penalty: a high-yield savings account or money market fund. Not in stocks, not in a certificate of deposit with an early withdrawal fee, and not in the same checking account you spend from. Interest earned matters less than availability.