Getting a perfect FICO credit score of 850 isn't easy, but after years of good credit behavior, personal finance coach Lynnette Khalfani-Cox achieved it in 2021.

A perfect score is rare — just 1.6% of Americans have one, according to FICO. And for Khalfani-Cox, The Money Coach and author of "Zero Debt: The Ultimate Guide to Financial Freedom," getting a perfect score wasn't necessarily a specific goal. 

Previously, her score was "in the high 800s." And she was fine with that, since any FICO score 800 or above is considered "exceptional" by the three major credit bureaus. Even without a perfect score, any borrower with exceptional status qualifies for loans and credit cards at the lowest possible interest rates.

However, receiving an email alert in 2021 about her perfect score was still an "oh, wow" milestone for Khalfani-Cox, who has written about her previous experiences dealing with debt, back when her credit score was in the 400s.

While achieving a perfect score might require some time and a mix of different types of loans, Khalfani-Cox says the following steps helped her get there.

1. Pay all your bills on time

One of the easiest ways to boost your credit is to simply never miss a payment. 

The biggest share of your FICO credit score — 35% — is based on how often you make minimum debt payments on time, whether that's for a credit card, personal loan or auto financing. 

A late payment can't be reported to credit reporting bureaus until it's at least 30 days past due, but a 30-day missed payment can reduce a very good or exceptional score by 63 to 83 points, according to FICO data. It also can stay on your credit report for up to seven years.

2. Avoid excessive credit inquiries

"Don't apply for credit unless you truly need it, because you don't want to have a whole bunch of inquiries that are lowering your credit score unnecessarily," says Khalfani-Cox. This is especially true if you're planning to apply for a big loan soon, like a mortgage.

An inquiry is a request to check your credit history, done with your consent, typically as part of an application for a loan or credit card.

These requests are often referred to as "hard inquiries" or a "hard pull" on your credit history. They can negatively impact your FICO score for up to a year, since excessive requests for new credit can be a red flag about your trustworthiness as a borrower.

3. Minimize how much debt you carry

How much credit you have available compared to how much you actually use is known as your credit utilization ratio, and it makes up 30% of your credit score. The more credit you have available, the higher your credit score will be. Experts generally recommend keeping your utilization rate under 10%. 

"A turning point in terms of me wanting to monitor and improve my credit rating happened after I started digging myself out of debt," says Khalfani-Cox. At one point earlier in her life, she had $100,000 in debt that took three years to pay off.

"My credit score jumped like 100 points after I finally paid off my credit card bills. That's when I noticed the really strong link between how I'm handling the debt side of the equation — specifically the credit card bills — and my credit score," she says.

4. Have a long credit history

The length of your credit history accounts for 15% of your score. Generally, the longer a loan or credit card has been active, the better it is for your credit score. Because of this, closing an account can temporarily ding your credit score by a few points.

This happened to Khalfani-Cox shortly after she achieved a perfect credit score. She had just paid off a mortgage loan and her score subsequently dropped by seven points, down to 843 from 850.

Having a long credit history may not be possible for younger borrowers, but they can begin to build it up by leaving their longest-standing account open.

5. Have a good mix of credit

Accounting for 10% of your credit score, having a mix of different types of credit accounts, including home loans, installment loans and revolving loans like credit cards, will improve your score. Khalfani-Cox had a good mix of loans, including multiple mortgages, which boosted her credit score.

"When you show that you can responsibly juggle all those types of loans, you get brownie points for that," says Khalfani-Cox. 

Of course, you probably shouldn't sign up for a mortgage or a personal loan just to chase a perfect score. But it is a factor to be aware of when you think about how your credit score is calculated.

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