We have a rewards checking account and want to ensure it is calculating the interest correctly on the statements. There are two tiers - 3.49% APY on balances $0.01 to $25,000 and 1.05% on balances over $25,000. I have used the FFIEC APY tool and all show OK without an APY violation.

However I just want to make sure it is correct because the APYE is not at those APY's. For one stmt, the APYE is showing 1.53%. Average ledger is $129,986.37 for 28 days and interest earned was $151.50.

Thanks for your help and input!

You are using tiering method B (interest rate for a tier only applies to balances in that tier). There is only one APYE, calculated on the entire balance. But the interest paid is based on two different rates paid on the two tiers. So the APYE is affected by the relative amount of the balances in each tier. In this case the balance in the first tier was $25k, and the balance in the second tier wsa $104,986.37. So a little less than 20% of the balance earned 3.49%, and a little more than 80% earned 1.05%. Even just doing the math roughly confirms your APYE is in the ballpark: 3.49 x ..20 + 1.05 x .80 = 1.53.

Or, to do it more precisely, $151.50 x 366/28 = $1,980.32. $1980.32/129,986.37 = 1.52. (I'm guessing the difference is due to rounding or carrying interest out to more decimals in the calculation or something like that.) That's not the official method from Reg. DD but it's easier to understand.

Thank you!!