9-Month CD Calculator

Calculate what a 9-month certificate of deposit earns at maturity — a term banks often use for their best promotional rates.

The 9-Month CD: The Promotional Term

Nine months is an odd term — and that's exactly why it exists. Banks use non-standard terms like 7, 9, 11, or 13 months for promotional offers designed to attract new deposits, and these promos frequently beat the bank's own standard 6 and 12-month rates. If you see a 9-month rate that looks unusually good, it probably is: that's the marketing budget talking, and you're allowed to take it.

What Can You Earn in 9 Months?

A $10,000 deposit at 4.35% APY grows to about $10,324 — roughly $324 in interest. The calculator above gives exact figures for any deposit and rate.

How to Play Promotional CDs

  • Read the renewal terms first. Promo CDs almost never renew at the promo rate — they roll into a standard (often mediocre) term. Diarize the maturity date with our Maturity Date Calculator.
  • Check the minimum deposit. Promos often require $5,000–$25,000 in new money.
  • Compare across banks, not within one. A 9-month promo at one bank may still lose to a standard 12-month rate elsewhere.

Is 9 Months the Right Term?

If the rate beats every 6 and 12-month offer you can find, yes. If it's merely close, prefer the standard terms — they're easier to ladder and renew. Odd terms are opportunistic buys, not portfolio building blocks.