You've found the perfect person, and you're ready to walk down the aisle. There's just one thing giving you pause: Your partner's credit score is under 600, and you're worried they might drag you down with them.

While it's true that your spouse's poor credit could come to affect you, your score won't take a hit just because you tied the knot. Your credit score is a measure of your financial responsibility, and it remains separate from your partner's -- even when the two of you are married. As long as you are responsible with the credit accounts in your name, your score will remain high.

But opening a joint account is another story.

Couple working out their finances

Image source: Getty Images.

Joint accounts are in both of your names, and if your spouse is running up huge debts that the two of you can't pay back, it will reflect badly on you, too. Any late payments, excessive credit usage, and accounts in collections will appear on both their credit report and yours. And the kicker is that you'll be penalized more than your partner, because higher credit scores tend to suffer bigger hits from financial mistakes than lower credit scores.

Your partner's poor credit score could also affect you when the time comes to buy a home or take out another type of joint loan. Some lenders may look at both of your credit reports when deciding whether to work with you, and even if your score is over 800, that may not be enough to compensate for your partner's below-average score.

How to improve your partner's bad credit

If you're concerned about how your partner's bad credit may affect your credit or your ability to get loans in the future, it's important to sit down with them and talk about it. If they're willing to work on improving their credit, there are things you can do to help them.

Consider making them an authorized user on your credit card. There's no credit check required, because they're not held responsible for paying the balance each month. That's still on you. However, in most cases, the account will still show up on their credit report, and they can reap the benefits of your good payment history each month.

You may also consider helping them get a secured credit card of their own. These cards are specially designed to help individuals with bad credit redeem themselves in the eyes of credit bureaus. Your partner will have to put down a security deposit -- usually around $200 -- and this amount is typically equal to the credit limit. Their payment history will be reported to the credit bureaus, just as if they were using a regular credit card. As long as they use the card responsibly and pay off their balance in full each month, their credit score will improve over time, and their security deposit will be refunded to them when they close their account.

From there, it all comes down to time and responsible habits. Make sure they pay their bills on time and don't use too much of their credit. Most experts recommend spending 30% or less of the credit that's available to you. So if you have a $10,000 credit limit, for example, you should limit yourself to $3,000 or less per month (and less is better). Over time, your partner will build a track record of responsible credit use, and older money mistakes will fall off of their credit report, raising their score.

If you're not comfortable opening a joint account with your partner right away, you should consider keeping your finances separate until their credit improves. You may also want to consider applying for any mortgages or loans in your own name if you're worried that your partner's score may lower your chances of approval. If necessary, you might ask a parent or another family member with better credit to go in on the loan with you.

Having a partner with bad credit isn't the end of the world, but it needs to be addressed if the two of you want the best chance of securing loans and good interest rates in the future. Work with your partner to improve their credit now before it becomes a problem.

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