How Mortgages Actually Work
Read a loan estimate, build an amortization schedule by hand, and tell a cheap mortgage offer from an expensive one.
This course is for members
$9 unlocks every course in the library, this one included, plus a credit to build a topic of your own and at least 10 new courses every month.
What you will learn about How mortgages actually work
The 7-day sprint
- What A Mortgage Actually Is. A mortgage is a loan of money plus a legal claim on your house that lets the lender take it if you stop paying, and everything else in the deal follows from those two facts.
- Amortization, The Engine Room. Your principal and interest payment stays the same every month, but the split between interest and principal changes every month, because interest is charged on whatever you still owe.
- PITI And The Escrow Account. Most monthly mortgage payments bundle principal, interest, property taxes, and insurance, and only the principal and interest half is truly fixed.
- Rate, Points, And APR. The interest rate sets your payment, but the APR is the yearly cost of the credit including points and other loan costs, which is why you compare offers on APR, not on rate alone.
- Down Payment, LTV, And Getting Rid Of PMI. Loan-to-value ratio decides whether you pay private mortgage insurance, and federal law fixes exactly when that insurance must come off.
- Loan Flavors And The Rules Behind Them. Fixed versus adjustable, conforming versus jumbo, and qualified versus not are three separate labels that together explain why your loan is priced and shaped the way it is.
- The Paper Trail And The Decision. Federal disclosure rules hand you two standardized documents and a three-day window precisely so you can compare offers and catch changes, and the whole course pays off when you use them.
The 80/20: the 6 concepts that matter most
- Amortization: the payment is fixed, the split is not
- APR, not the rate, is the price of the loan
- Loan-to-value decides your cost and your insurance
- Escrow makes a fixed payment un-fixed
- Fixed versus adjustable is index plus margin plus caps
- Conforming limits and the secondary market shape your options
The core idea, explained like you are 5
A mortgage payment is rent on the money you still owe plus a slice of that money handed back, so the balance shrinks a little every month until it hits zero.
Then the quiz and the ladder
10 questions that correct you when you are wrong, and beginner, intermediate, advanced levels, each with a practical exercise.
Created Sep 13, 2026. No mistakes have been reported by learners.
Written from these sources
- How does paying down a mortgage work? | Consumer Financial Protection Bureau, consumerfinance.gov. day 2 and the amortization concept in Pareto.
- Know Before You Owe: Mortgages | Consumer Financial Protection Bureau, consumerfinance.gov. day 7 Loan Estimate and Closing Disclosure rules.
- Shopping for a Mortgage FAQs | Consumer Advice, consumer.ftc.gov. day 4 APR versus rate, day 7 timing.
- Amortized Loan: Definition, How to Calculate, Example Schedules | Chase, chase.com. day 2 formula and the $200,000 at 5% example.
- Amortization Calculator – Free Amortization Schedule, amortization-calc.com. day 2 row method and 6.50% front-loading example.
- How is an Amortization Schedule Calculated?, cis.temple.edu. day 2 step-by-step $250,000 at 5% walkthrough.
- Amortization Calculator | Bankrate, bankrate.com. day 1 common loan term lengths.
- Mortgage Amortization Calculator: Generate Your Loan Amortization Schedule & Full Amortization Schedule | Rocket Mortgage, rocketmortgage.com. day 7 what calculators hide, prepayment caution.
- Mortgage Rates - Freddie Mac, freddiemac.com. day 4 rate levels, survey methodology and dates.
- FHFA Announces Conforming Loan Limit Values for 2026 | FHFA, fhfa.gov. day 6 and Pareto 2026 conforming loan limits.
- FHFA Conforming Loan Limit Values | FHFA, fhfa.gov. day 6 HERA formula and announcement timing.
- Loan Limits | Fannie Mae, singlefamily.fanniemae.com. day 6 jumbo definition and original loan amount rule.
- U.S. Federal Housing (FHFA) Announces Conforming Loan Limit Values for 2026 | Fannie Mae, capitalmarkets.fanniemae.com. day 6 secondary market plumbing and high-cost examples.
- eCFR :: 12 CFR 1026.43 -- Minimum standards for transactions secured by a dwelling., ecfr.gov. day 6 and expert stage qualified mortgage features.
- 1 BILLING CODE: 4810-AM-P BUREAU OF CONSUMER FINANCIAL PROTECTION, files.consumerfinance.gov. day 6 price-based general QM replacing 43% DTI.
- § 1024.17 Escrow accounts. | Consumer Financial Protection Bureau, consumerfinance.gov. day 3 escrow cushion, aggregate accounting, annual analysis.
- eCFR :: 12 CFR 1024.17 -- Escrow accounts., ecfr.gov. day 3 escrow limits and statement deadlines.
- For an adjustable-rate mortgage (ARM), what are the index and margin, and how do they work? | Consumer Financial Protection Bureau, consumerfinance.gov. day 6 index plus margin for ARMs.
- January 2014 Consumer handbook on adjustable-rate mortgages, files.consumerfinance.gov. day 1 servicer point, day 6 ARM caps and SOFR.
- When can I remove private mortgage insurance (PMI) from my loan? | Consumer Financial Protection Bureau, consumerfinance.gov. day 5 PMI termination at 78 percent and midpoint.
- Homeowners Protection Act (PMI Cancellation Act) | NCUA, ncua.gov. day 5 HPA rules, original value, high-risk loans.
- Private Mortgage Insurance (PMI), tdi.texas.gov. day 5 HPA effective date and cancellation option.
- Amortization schedule, en.wikipedia.org. definition of an amortization schedule.