My dad says to leave a balance on my card to build credit. Is he right?

The question

An illustrative letter.

The answer

My dear, your father wants you to start well, and that is a lovely thing. He is half right, too: a card that sits in a drawer does very little for you, and lenders do want to see you use credit. Where the old idea goes wrong is in thinking you must owe money, and pay interest on it, for that use to count. You do not. I spent many years on the lending side of the desk, and I can tell you that a borrower who pays in full every month is exactly the borrower a lender hopes for.

Where does the idea of carrying a balance come from?

It is one of the most common money myths there is. In a 2023 survey reported by the company behind the FICO score, nearly half of the people asked believed that carrying a balance helps your credit score. It sounds sensible, because a card company earns money when you pay interest. But your credit score is not a measure of how much interest you have paid. It is a measure of how reliably you handle what you borrow.

What actually builds your credit?

FICO scores, the ones most lenders use, weigh five things. Payment history counts for about 35 percent: did you pay on time? Amounts owed count for about 30 percent: how much of your available credit are you using? The length of your credit history, the mix of credit you have and how much new credit you have recently applied for make up the rest.

Notice what is missing from that list. Nothing in it rewards you for paying interest. Paying on time and keeping balances low are the two biggest parts of the score, and you can do both perfectly while paying your card in full every single month.

What is credit utilization, and why does it matter on a $500 card?

Utilization is the share of your credit limit you are using, based on the balance your card company reports. Most card companies report your balance once a month, on the date your statement closes. If your statement shows $200 on a $500 limit, the credit bureaus see 40 percent, even if you pay all of it the next day.

A common rule of thumb, which the Consumer Financial Protection Bureau repeats, is to keep it under 30 percent, and lower is better. On your card, that means a statement balance under $150. With a small limit, this is easy to cross without noticing, so it helps to keep only a few small, regular charges on the card. If a bigger purchase comes along, you can pay part of it before the statement closes.

What does carrying a balance really cost?

Most cards give you a grace period: if you pay the full statement balance by the due date, you pay no interest on your purchases. By law, card companies must send your bill at least 21 days before the payment is due, so you have time. Carry part of the balance, and interest starts on what is left. The Federal Reserve's figures put the average rate on cards that charge interest at about 22 percent a year in 2026.

On a small balance, the cost looks small: a few dollars a month. But it buys you nothing, and you may lose your grace period on new purchases until you pay in full again. The habit is the bigger danger. Balances that are carried tend to grow, and many people who struggle with card debt later started exactly this way.

How do I build credit with my first card, then?

• Give it one small job. Many people put a single regular bill on the card, such as a phone bill, so it is used every month.
• Pay the full statement balance automatically. Most card companies let you set automatic payment for the full statement balance. Choose that, not the minimum.
• Learn your two dates. The statement closing date is when your balance is reported. The due date is when your payment is due. They are usually a few weeks apart.
• Keep the reported balance low. Under $150 on a $500 limit is a good target.
• Be patient. A FICO score needs at least one account that has been open for six months or more. A year or two of on-time payments builds a solid start.

The checklist further down gathers these in one place.

How do I talk to my father about it?

Gently, and with thanks. He gave you good instincts: use the card, and take your credit seriously. You might show him your statement after a few months, paid in full, with no interest charged, and your credit report growing. Most parents are delighted to learn their child can build credit and pay nothing for it.

What does good credit open up for you?

You are starting at about twenty, which is a real gift. By the time you want an apartment in your own name, a car loan or one day a mortgage, you could have years of clean, on-time history behind you. That history will save you money on every loan you ever take. All it asks of you is a little attention once a month, and no interest at all.

One thing to do this week

Set your card to pay the full statement balance automatically each month, and write down your statement closing date.