By James Walker — CFP® candidate, Boston MA · Updated January 2026
If you’ve ever been quoted a 7.5% mortgage rate when your friend got 6.2%, the difference was probably your FICO score. A 100-point jump can save you tens of thousands of dollars in interest over your lifetime. Let’s break down exactly how it works and what actually moves the number — not the TikTok myths.
What is a FICO credit score and who calculates it?
FICO is the brand name of the most widely used credit scoring model, developed by the Fair Isaac Corporation. The three major credit bureaus — Experian, Equifax, and TransUnion — each maintain a credit file on you, and FICO turns that file into a score between 300 and 850.
The CFPB has a great primer on the basics of credit scores if you want the official explanation.
General FICO bands (lender ranges vary):
- 800–850: Exceptional — best rates available
- 740–799: Very Good
- 670–739: Good (national average sits around here)
- 580–669: Fair — you’ll get approved but pay more
- 300–579: Poor — many denials, sky-high rates
What are the five factors that build your FICO score?
1. Payment History (35%)
Whether you pay your bills on time. A single 30-day late payment can drop a clean 780 score by 80–110 points. Late payments stay on your report for 7 years. This is the single biggest lever — never miss a payment. Set autopay for at least the minimum on every card.
2. Amounts Owed (30%)
Primarily your credit utilization ratio — the percentage of your credit card limits you’re using. Under 30% is OK, under 10% is ideal, and 1–3% on at least one card with the rest at zero is the sweet spot for top-tier scores.
3. Length of Credit History (15%)
How long your accounts have been open. Average age of accounts matters — this is why closing your oldest card is usually a mistake.
4. New Credit (10%)
Hard inquiries from applying for new credit. Each inquiry costs ~5 points temporarily. Multiple inquiries for the same product (mortgage, auto) within ~45 days count as one inquiry.
5. Credit Mix (10%)
The variety of credit types (revolving cards, installment loans, mortgages). You don’t need to chase mix — just don’t have only one card.
How fast can you raise your credit score by 100 points?
In my experience tracking my own and friends’ reports while preparing for CFP exam credit-coursework: 60–120 points in 6 months is realistic if you start in the 580–680 range. Above 740, gains slow dramatically.
The 6-month 100-point action plan
Month 1 — Pull and review your reports
Get free copies of all three reports at AnnualCreditReport.com (the federally authorized site). Look for:
- Late payments that aren’t actually late
- Accounts you don’t recognize
- Old debts that should have aged off (7 years from first delinquency)
- Wrong balances
Dispute errors through each bureau in writing. The CFPB’s credit dispute tools are the right starting point.
Month 2 — Set autopay everywhere, kill late payments forever
Every card on at least minimum autopay. Every loan on autopay. Set calendar reminders. One missed payment can undo 6 months of progress.
Months 2–4 — Crush credit card utilization
This is the single fastest mover. If you owe $4,500 across cards with $5,000 total limits (90% utilization), you’re leaving 60+ points on the table. Get utilization under 30%, then under 10%.
Two tactics:
- Pay down balances using the avalanche method (highest APR first — see our avalanche vs snowball guide)
- Ask for credit limit increases on existing cards. A higher limit lowers your utilization without you doing anything else. Soft-pull increases (Capital One, Discover) don’t cost you points.
Months 4–6 — Pay before the statement closes
Your card reports the statement balance to the bureaus, not the post-payment balance. Pay your card down to ~1% utilization before the statement closes each month. Score boost: 10–25 points.
What hurts your credit score the most?
- Missing a payment by 30+ days (60–110 point drop)
- Collections account (50–100 point drop)
- Maxing out a card (40–80 point drop)
- Closing your oldest card (10–30 point drop over time)
- Bankruptcy (130–240 point drop, stays 7–10 years)
- Applying for many cards in a short window (10–30 point drop)
Does checking your own credit score lower it?
No. Pulling your own report is a soft inquiry — it never affects your score. Same for the score you see in Credit Karma, your bank app, or Experian’s free portal. Only hard inquiries (when a lender pulls credit for an application) ding your score, and even then only 3–5 points temporarily.
Should I close old credit cards I don’t use?
Usually no. Closing a card removes its credit limit (raising your utilization) and eventually drops it from your average-age calculation. Better: keep it open with a tiny recurring charge (like a $10/mo subscription) on autopay so the issuer doesn’t close it for inactivity. The exception: cards with high annual fees you can’t justify — downgrade to a no-fee version instead of closing.
And if you need help with the cash-flow side first, our guides on building a monthly budget and reducing monthly expenses are the prerequisite.
What about credit repair companies?
The CFPB is blunt: credit repair companies generally can’t do anything you can’t do yourself for free. Many violate the Credit Repair Organizations Act. Skip them. Dispute errors yourself, set autopay, and pay down balances. There is no legal magic.
Frequently Asked Questions
How often is my credit score updated?
Credit reports update every time a creditor reports new data — usually monthly when each card’s statement closes. Your FICO score recalculates whenever it’s pulled. So a single big paydown can show up within 30 days, but the maximum impact usually takes 2–3 statement cycles. Don’t expect a big jump within a week of paying down debt.
Is FICO the same as VantageScore?
No. VantageScore is a competing model from the three bureaus. Most lenders — especially for mortgages and auto loans — use FICO. Credit Karma shows VantageScore (TransUnion and Equifax versions). The two scores can differ by 20–60 points. When applying for a loan, ask which model the lender uses.
Will paying off a collection account remove it from my report?
Not automatically. Paying it changes the status to “paid” but the account stays on your report for 7 years from the original delinquency date. Newer FICO models (FICO 9 and 10) ignore paid collections, but many lenders still use FICO 8 which does not. Ask the collector for a “pay for delete” agreement in writing before paying.
How much does a hard inquiry hurt my score?
Typically 3–5 points for 12 months, with the impact fading over time. Inquiries fall off entirely after 24 months. Multiple inquiries for the same purpose (rate-shopping a mortgage or auto loan) within roughly 45 days count as one inquiry under FICO’s deduplication rule. Don’t avoid rate-shopping out of fear — it’s explicitly protected.
Can I get a mortgage with a 620 credit score?
Yes — FHA loans accept FICO scores as low as 580 with 3.5% down. But the rate will be meaningfully higher than at 740+. On a $350K mortgage, the difference between a 620 and 740 score can be 0.75–1.25 percentage points, or roughly $250–$400 more per month. Improve your score first if you can wait 6–12 months.