Interest posts on a schedule set by your bank, not continuously
Your bank does not add interest to your account every day, even though interest accrues (builds up) daily. Instead, your bank calculates the interest you have earned and deposits it into your account on a fixed schedule — usually monthly, quarterly, or annually. The exact timing depends on your bank's terms and the type of savings account you hold.
Most banks post interest monthly or quarterly. Some online banks post monthly; some post daily. A few traditional banks still post only once a year, though this is less common now. You can find your bank's posting schedule in your account agreement or by calling customer service and asking directly: "How often does interest post to this account, and on what date?"
The interest rate itself may change, but the posting schedule stays the same unless your bank notifies you of a change. If your bank changes the posting frequency, they must tell you in advance — usually 30 days.
Key Takeaways
- Interest posts on a fixed schedule (usually monthly or quarterly), not every day, even though it accrues daily.
- Your bank's account agreement or customer service can tell you the exact posting date and frequency for your specific account.
- The amount of interest you receive depends on your account balance, the annual percentage yield (APY), and how long the money sits in the account.
- Interest posted to your account is yours to keep; you do not have to do anything to receive it once it posts.
- If your bank changes the posting schedule, they must notify you at least 30 days in advance.
How the posting date affects the amount you receive
The posting date matters because interest is calculated on your average daily balance during the period before it posts. If you deposit money on the 15th of the month and your bank posts interest on the last day of the month, you earn interest for only half the month on that deposit. If you withdraw money before the posting date, you lose the interest that would have been calculated on that amount.
Some banks use the "daily balance method," which means they calculate interest on your balance every single day, then add it all up and post the total on the posting date. Other banks use the "average daily balance method," which averages your balance over the entire period. A few use the "minimum balance method," which pays interest only on the lowest balance you held during the period. Your account agreement should state which method your bank uses.
The difference between these methods can be small or significant depending on how much your balance changes. If your balance stays steady, the method matters less. If you make large deposits or withdrawals, the method can change how much interest you receive by a few dollars or more.
Why the interest rate and APY are not the same thing
Your bank advertises an annual percentage yield (APY), not just an interest rate. The APY includes the effect of compounding — the process of earning interest on your interest. If your bank posts interest monthly, you earn interest on January's interest in February, and on both January and February's interest in March, and so on.
The difference between the stated rate and the APY is usually small — often less than 0.1 percent — but it adds up over time, especially with larger balances. A savings account with a 4.5 percent APY will earn more than one with a 4.5 percent stated rate, because the APY already accounts for compounding.
When comparing savings accounts, always compare the APY, not the rate. The APY is the true picture of what you will earn over a year.
What happens if your bank changes the interest rate
Banks change interest rates frequently, especially when the Federal Reserve raises or lowers its benchmark rate. When your bank lowers the rate on your savings account, the new rate applies to interest posted after the change takes effect — not to interest already posted. Your bank must notify you before the rate changes, usually 30 days in advance.
If your bank raises the rate, the increase also applies to interest posted after the effective date. You do not have to do anything; the new rate is automatic. If you disagree with a rate decrease, you can move your money to a different bank, but you cannot reverse a rate change that has already taken effect.
Some banks offer promotional rates for new accounts — for example, 5.0 percent APY for the first three months, then 4.5 percent after that. The terms of the promotion are in your account agreement. Read them carefully so you know when the promotional rate ends.
How to track when interest posts to your account
The easiest way to see when interest posts is to check your account statement. Most banks provide statements monthly or quarterly, and each statement shows the interest posted during that period. Online banking also shows deposits in real time, so you can watch for the interest deposit on the expected date.
If you do not see interest posted on the date you expected, wait a few business days — posting sometimes happens over a weekend or holiday. If it still has not appeared after a week, contact your bank. Interest should post automatically; if it does not, there may be an error in your account or a technical problem.
You can also ask your bank for a written copy of your account agreement, which will state the exact posting schedule. Some banks list this information on their website under "Account Terms" or "Disclosures."
Interest on money you withdraw before the posting date
If you withdraw money before interest posts, you lose the interest that would have been earned on that amount. For example, if you have $5,000 in your account on the 1st of the month and withdraw $2,000 on the 20th, the interest posted on the 30th will be calculated on a lower average balance — not on the full $5,000.
This is why the timing of deposits and withdrawals can matter if you are trying to maximize interest. If you know interest posts on the last day of the month, depositing money early in the month means it earns interest for the full month. Withdrawing money late in the month means you lose interest on that amount for the entire period.
For most people, this difference is small. But if you are moving large sums or managing multiple accounts, paying attention to posting dates can add up over time.
Frequently Asked Questions
Can I withdraw my interest without losing the principal?
Yes. Once interest posts to your account, it becomes part of your balance and you can withdraw it without affecting the money you originally deposited. The interest is yours to keep. If you withdraw only the interest and leave the principal, you continue earning interest on the principal at the same rate.
What if my bank posts interest but I do not see it in my account?
Check your statement or online banking to confirm the deposit went through. Interest posts automatically, so if it does not appear within a few business days of the expected date, contact your bank. There may be a delay due to a holiday or weekend, or there could be an error in your account.
Does interest post even if my account balance is very low?
Yes, as long as your account is open and active. However, if your balance is below the minimum required to earn interest (some accounts have a minimum), no interest will post. Check your account agreement to see if there is a minimum balance requirement for earning interest.
If I move my money to a different bank, do I lose the interest I already earned?
No. Interest that has already posted to your account is yours. When you transfer money to a new bank, the interest you earned stays with you. You only lose future interest that would have been earned at the old bank.
Why does my interest seem lower than the APY advertised?
The advertised APY assumes your money stays in the account for a full year without deposits or withdrawals. If you withdraw money partway through the year, or if your balance is lower than expected, the actual interest you earn will be less than the full APY. Also, if the bank lowered the rate during the year, the interest earned before the rate change was higher than after.