These services provide you with free credit monitoring alerts so you can spot fraud early

Regularly monitoring your credit can help you spot signs of potential fraud, but it can be hard to do on your own. While there are credit monitoring services that can make catching fraud easier, many charge a monthly fee.

Thankfully, a handful of major financial institutions offer free credit monitoring alerts to consumers, regardless of whether you have an account with them.

These services backed by American Express, Capital One, Chase and Experian are a great way to stay on top of changes to your credit file — whether that's an increase in your card balance or a new account opened in your name. Some services even scan the dark web for your personal information. Others let you simulate how certain actions, such as paying off debt or opening a new account, can impact your credit score.

Below, CNBC Select reviews the top credit monitoring alert services that are open to anyone and are completely free. (See our methodology for more information on how we chose the best services.)

• What do credit monitoring alert services do?
• Can credit monitoring alert services prevent fraud?
• How to prevent fraud

Credit monitoring alert services do just what the name suggests — monitor your credit and alert you of any changes. While you can do this on your own, it’s nearly impossible to stay on top of changes 24/7, so signing up for one, or more, of these free services is a good idea.

The exact alerts you receive vary by service, but generally include the following:

• Hard inquiries on your credit report, such as someone applying for credit in your name
• New accounts opened in your name
• Balances and payments on your credit products
• New address or name changes to your credit file
• Public records, such as bankruptcies
• Personal information on the dark web, such as your social security number, email address and passwords (only three out of five services mentioned above offer this)

While credit monitoring alert services routinely check for signs of possible fraud, these services only provide alerts. Fraud can still occur, but these tools can give you an early notice of changes to your credit file so you can take action ASAP.

No, credit monitoring alert services aren’t the answer to preventing fraud. In fact, there’s no real way to completely stop fraud from happening, but you can take actions that limit the chances you become a victim.

Here are some things credit monitoring alert services don’t do:

• Stop someone from applying for credit and opening new accounts in your name
• Keep your information safe from data breaches
• Prevent your credit card from being skimmed
• Tell you if someone withdraws money from your bank account
• Warn you if someone files a tax return in your name and collects your refund
• Stop phishing emails
• Report fraud
• Fix credit report errors
• Freeze your credit

There are numerous ways someone can commit credit card fraud or identity theft, but there are actions you can take to protect your information. Since there’s no way to prevent fraud from happening entirely, follow these tips to help limit your chances of becoming a victim of fraud.

1. Review your credit card transactions
2. Sign up for transaction alerts
3. Freeze your credit
4. Sign up for an identity theft protection service
5. Don’t use public WiFi
6. Use websites that start with “https” (not just http, which is less secure)
7. Don’t answer spam calls or texts
8. Verify deals from social media ads
9. Don’t click on links or open attachments from unknown senders
10. Opt-out of saving your credit card information
11. Use virtual card numbers
12. Set strong passwords
13. Turn on two-factor authentication

At CNBC Select, our mission is to provide our readers with high-quality service journalism and comprehensive consumer advice so they can make informed decisions with their money. Every credit monitoring review is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of credit monitoring products. While CNBC Select earns a commission from affiliate partners on many offers and links, we create all our content without input from our commercial team or any outside third parties, and we pride ourselves on our journalistic standards and ethics. See our methodology for more information on how we choose the best free credit monitoring services.

To determine which credit monitoring alert services offer the most benefits to consumers, CNBC Select analyzed and compared services offered by major financial institutions that are available to anyone for free.

When ranking the best free credit monitoring services, we focused on the following features:

• Open to anyone: Services had to be open to anyone, regardless if you’re an account holder at the financial institution.
• Number of credit bureaus monitored: Services that monitor credit reports from more than one credit bureau were ranked higher since it’s rare for free services to monitor all three bureaus.
• The credit scoring model used: If users receive updated FICO Scores, the service was ranked higher since lenders use FICO Scores in roughly 90% of lending decisions. We found that the majority of free services use VantageScore.
• Dark web scanning: If the service checks the dark web for your name, social security number, address and other personal information, it was ranked higher.
• Identity theft insurance: We considered whether the services offered identity theft insurance and looked at the amount you’re covered up to.

Keep in mind that credit monitoring alerts can only show you signs of potential fraud, not fix or prevent any errors.