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L.13 · BEGINNER · 4 MIN

Credit Score Mechanics — All Five Factors

Your credit score follows you into every major financial decision: mortgage approval, apartment rental, car loan rates, and sometimes even job applications. Most people know the headline rule — keep utilization low — but that is only 30% of the story. Understanding all five FICO factors, how the score is calculated on a specific snapshot day, and the 12-month seasoning lenders require before mortgage approval can save you years of rebuilding time and thousands of dollars in higher interest rates.

Quiz · 5 questions ↓
§ 01
FICO FactorWeightWhat HelpsWhat Hurts
Payment History35%Every on-time payment, including minimum paymentsA single 30-day late payment; collections; charge-offs
Credit Utilization30%Balances well below 30% of each card's limit (under 10% for top scores)Carrying a high balance even if you pay in full — the snapshot captures statement-date balance
Length of Credit History15%Long average account age; oldest account ageClosing old cards reduces average age; opening many new accounts also lowers average age
Credit Mix10%Both revolving (credit cards) and installment (auto loan, student loan) accountsOnly one type of credit; no installment history
New Credit10%Minimal recent hard inquiries; no cluster of new accountsMultiple hard inquiries in a short window; opening several cards at once
§ 02

The snapshot day matters. Your utilization ratio is calculated from your statement-closing balance — not whether you paid the bill. If your card has a $10,000 limit and you charged $7,000 this month (even planning to pay it in full), the bureau reports 70% utilization on the day the statement closes. To show low utilization, pay down the balance before the statement closing date, not just by the payment due date.

§ 03

The authorized-user shortcut: if a parent or spouse adds you as an authorized user to a card with a long history, low utilization, and perfect payment record, that account's entire history can appear on your credit report — instantly boosting your average account age and payment history. The effect is legitimate and the same technique used by credit-repair services. The risk: if the primary cardholder misses payments or runs up balances, the damage also hits your report. Only use the authorized-user path with someone you trust completely, and monitor your report monthly.

§ 04

Do not close old credit cards. Many people close cards they no longer use, thinking it looks cleaner. It does the opposite: (1) it reduces your total available credit, raising utilization on other cards; (2) it lowers your average account age and eliminates your oldest account's contribution to length-of-history. Keep old cards open with a small recurring charge (e.g., a $5 streaming subscription) to prevent the issuer from closing them for inactivity.

§ 05
Utilization Ratio = Total Balances / Total Credit Limits (across all revolving accounts)
§ 06

Hard inquiries vs. soft inquiries: only hard inquiries affect your score. Hard inquiries happen when you apply for new credit (credit card, auto loan, mortgage). Soft inquiries — checking your own credit, employer background checks, pre-qualification offers — do not affect your score at all. Rate shopping for a mortgage or auto loan within a 14–45 day window counts as a single inquiry (depending on the scoring model), so do not delay shopping out of inquiry fear.

§ 07

Most conventional mortgage lenders want to see at least 12 months of clean credit history before approving a prime-rate mortgage. 'Clean' means no 30-day lates, no new derogatory marks, and stable utilization. If you plan to buy a home in the next 12–18 months: (1) do not open new credit cards; (2) do not close old ones; (3) pay every bill on time — one slip can delay your mortgage timeline by months; (4) pay down balances to under 10% utilization on each card before applying.

§ 08

FICO scores range from 300 to 850. Lenders typically use score bands: 760+ (best rate tier), 740–759, 720–739, 700–719, 680–699, and below 680 (subprime or denial territory for conforming mortgages). The rate difference between a 760+ score and a 680 score on a $400,000 30-year mortgage can be 0.5–1.0 percentage points — equal to $50,000–$100,000 in additional lifetime interest. Going from 720 to 760 often saves more than going from 680 to 720.

§ 09
Pull your free credit report at annualcreditreport.com (federally mandated; no credit card required). Review each tradeline: (1) Are all accounts listed correct? (2) Are there any late payments you do not recognize? (3) What is the oldest account on your report? Disputing errors on your report can raise your score quickly when the error involves a false late payment.
§ 10
You have a credit card with a $8,000 limit. You charged $6,000 this month but plan to pay the full balance before the due date. What is your reported utilization?
Five questions · AI feedback

Sit with the ideas.

Your credit report shows: Account A (age 8 years, $5,000 limit, $0 balance, never late), Account B (age 2 years, $3,000 limit, $1,500 balance, never late), Account C (age 6 months, $2,000 limit, $0 balance, opened last month). You are thinking of closing Account A because you never use it. What is the most likely effect on your credit score?

Why:
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