Model tiered platinum versus standard savings APY with deposits and daily compounding.
Overview
Tiered savings products often pay one APY on smaller balances and a higher APY once you meet a platinum or premium minimum. The break-even question is whether keeping extra cash in the account to qualify beats earning a lower rate elsewhere.
This calculator lets you assign different APYs to balance tiers you define, add monthly deposits, and see projected interest. Use it to test how long it takes to reach a tier threshold through savings alone.
Not affiliated with CIT Bank/Merrill. Tier thresholds and rates change; verify current product sheets before transferring large balances.
Steps
Funds already in or moving to savings.
Rate below tier threshold.
Higher rate at qualifying balance.
Balance required for platinum rate.
Optional recurring savings.
Review interest versus staying sub-tier.
Math
Piecewise daily compounding at APY_standard or APY_platinum based on balance vs tier minimum
When balance crosses tier minimum, subsequent daily accrual uses the higher APY on qualifying portion per tool rules.
Worked cases
Track month balance crosses tier
Platinum APY applies after threshold month.
Full balance at platinum APY
Higher interest than standard tier scenario.
Never triggers platinum APY
May still beat checking if APY competitive.
Why use this
Questions