Calculate cash advance withdrawal, total repaid, months to payoff, or an implied monthly rate using a simple-interest model. Select the value to solve for and enter the other three.
Cash Advance Interest Formula
The calculator uses simple monthly interest on the full withdrawal, which remains outstanding until one final repayment. It treats the rate as a percent per month and excludes interim payments, fees, compounding and rate changes. Actual credit card interest can depend on daily balances and issuer terms; this is not a statement payoff calculation.
Rearranged formulas for the missing value:
- TR = total amount repaid for the cash advance
- W = total cash advance withdrawal amount
- I = implied interest rate, as a percent per month
- M = number of months until the cash advance is paid off
If you enter the withdrawal amount, monthly interest rate, and number of months, the calculator finds the total amount repaid. If you enter the total repaid instead of one of those values, it rearranges the same formula to solve for the missing withdrawal amount, payoff time, or implied monthly interest rate.
Monthly Cash Advance Rate Reference
Cash advance costs are often quoted as APR, but this calculator takes a monthly percentage. APR divided by 12 gives a nominal monthly approximation for this simple-interest model, not an exact daily-balance or fee-inclusive rate. The table gives illustrative rates, not current card offers.
| APR | Approx. Monthly Rate | Interest on $1,000 for 1 Month |
|---|---|---|
| 24% | 2.00% | $20.00 |
| 30% | 2.50% | $25.00 |
| 36% | 3.00% | $30.00 |
| 48% | 4.00% | $40.00 |
Example Calculations
Example 1: Find the total amount repaid
You take a $500 cash advance, the monthly interest rate is 3%, and it takes 4 months to pay off.
The total amount repaid is $560.00.
Example 2: Find the implied monthly interest rate
You withdrew $800 and repaid $920 after 5 months.
The implied interest rate is 3.00% per month.
FAQ
Does this include cash advance fees?
No separate fees are modeled. Enter total repaid excluding fees when inferring a pure interest rate. If fees are included in repayment, the inferred percentage represents total borrowing cost under this simplified model rather than just interest. Cash advances may also carry flat or percentage transaction fees.
Is cash advance interest usually charged monthly?
Many issuers calculate interest using daily or average daily balances, and some compound interest daily. This calculator assumes a constant balance and simple monthly interest. APR divided by 12 is only a nominal monthly approximation; consult the card agreement and statement for the actual charge. See the CFPB explanation of credit card interest.
Why is the cash advance interest higher than a normal purchase?
Cash advances often have a higher APR than purchases, and interest may start immediately with no grace period. That means the cost can grow from the day you take the advance until it is fully paid off.
