- Official section
- National IV: Financing
- Broker weight
- 10% of the national broker portion
- Expected scored items
- Financing accounts for about 10 of 100 items
Illinois exam glossary
Adjustable-rate mortgage
An ARM is not simply a mortgage with a rate that goes up. It is a rulebook: one index, one margin, specific change dates, specific caps and floors, a rounding method, and a payment recalculation. The exam becomes manageable when you run those rules in order instead of reacting to the product label.
Last updated: August 1, 2026
What does this exam area cover?
Short answer: An adjustable-rate mortgage is a loan whose interest rate may change after closing according to contractual terms. The adjusted rate usually begins with a current index plus a fixed margin, then applies rounding, an initial adjustment cap, later periodic caps, a lifetime maximum, and any floor. A 5/1 ARM is generally fixed for 5 years and adjusts annually after that; a 5/6m ARM generally adjusts every 6 months after the initial 5 years. When the rate changes, the principal-and-interest payment is commonly recalculated using the unpaid balance, new rate, and remaining term.
This guide uses CFPB ARM guidance updated through May 2026, the current CHARM booklet, current Regulation Z sections 1026.19, 1026.20, and 1026.37 with official interpretations, current Fannie Mae/Freddie Mac 30-day Average SOFR uniform instruments, and the PSI Illinois exam outline, all checked through August 1, 2026. ARM contracts vary in index, lookback, rounding, caps, floors, payment frequency, conversion, interest-only, negative-amortization, and replacement-index terms. The executed documents govern a real loan.
What is on the official outline?
- Topic
- Classify the ARM
- What to know
- Adjustable rate, variable rate, hybrid ARM, fully adjustable ARM, fixed initial period, change date, payment change, closed-end credit, dwelling, and principal residence
- Best exam move
- Ask whether the interest rate may change under an unknown future index or formula after closing.
- Topic
- Decode the product label
- What to know
- 3/1, 5/1, 7/1, 10/1, 5/6m, initial period, years, months, first adjustment, later frequency, shorthand, and note terms
- Best exam move
- First number is the initial fixed period; second is the later adjustment interval in the label's stated unit.
- Topic
- Identify the index
- What to know
- External benchmark, market movement, administrator, publication source, 30-day Average SOFR, Treasury index, prime rate, current value, lookback, and availability
- Best exam move
- The index moves with the market and must be the exact index named in the contract.
- Topic
- Identify the margin
- What to know
- Contract spread, percentage points, creditor pricing, fixed margin, index addition, fully indexed rate, comparison shopping, replacement margin, and note
- Best exam move
- Index plus margin produces the preliminary fully indexed rate before caps and rounding.
- Topic
- Calculate the preliminary rate
- What to know
- Current index, margin, addition, percentage points, decimal conversion, negative index treatment, lookback date, and current change date
- Best exam move
- Write index + margin first and delay cap analysis until the uncapped rate is visible.
- Topic
- Apply rounding
- What to know
- Nearest one-eighth, 0.125 percentage point, nearest basis point, contract convention, before caps, after caps, current uniform note, and exact result
- Best exam move
- Use only the rounding rule supplied by the note or question; do not invent one.
- Topic
- Apply the initial cap
- What to know
- First adjustment, initial rate, increase limit, decrease limit, percentage points, first change, teaser rate, fully indexed rate, and constrained result
- Best exam move
- Compare the candidate rate with the maximum and minimum allowed at the first change.
- Topic
- Apply subsequent caps
- What to know
- Later adjustment, prior rate, periodic increase, periodic decrease, change frequency, carryover, current index, and constrained rate
- Best exam move
- A later cap usually measures from the immediately preceding contractual rate, not always from the initial rate.
- Topic
- Apply lifetime limits
- What to know
- Maximum rate, minimum rate, lifetime cap, floor, initial rate reference, stated absolute rate, ceiling, downward limit, and loan term
- Best exam move
- The periodic cap cannot authorize a rate above the lifetime maximum or below the contractual floor.
- Topic
- Recalculate the payment
- What to know
- Unpaid principal, adjusted rate, remaining term, substantially equal payments, maturity, amortization, principal, interest, payment date, and rounding
- Best exam move
- Do not apply the new rate to original principal if the question gives a current unpaid balance.
- Topic
- Separate rate and payment caps
- What to know
- Interest-rate cap, payment cap, payment change, negative amortization, unpaid interest, recast, balance cap, consumer disclosure, and contract
- Best exam move
- A rate cap limits the rate; a payment cap limits payment and can create different balance consequences.
- Topic
- Identify a teaser rate
- What to know
- Discounted initial rate, start rate, introductory period, fully indexed rate, index unchanged, first reset, payment shock, points, and affordability
- Best exam move
- The rate can jump from a discount to index plus margin even when the index is flat.
- Topic
- Recognize a floor
- What to know
- Minimum rate, margin floor, initial-rate floor, absolute floor, downward cap, negative index, contract language, and lower bound
- Best exam move
- A falling index does not guarantee an equal rate decrease when the floor binds.
- Topic
- Read the AIR table
- What to know
- Loan Estimate page 2, index, margin, initial interest rate, minimum rate, maximum rate, first change, subsequent frequency, first-change limit, and later limit
- Best exam move
- Use the Adjustable Interest Rate table to map the formula and boundaries before comparing offers.
- Topic
- Read program disclosures
- What to know
- Application timing, CHARM booklet, program disclosure, index history, payment example, caps, frequency, conversion, demand feature, negative amortization, and prepayment
- Best exam move
- Program disclosure explains the offered ARM plan; the Loan Estimate applies terms to the proposed transaction.
- Topic
- Read the initial notice
- What to know
- Section 1026.20(d), first adjustment, separate document, 210 days, 240 days, adjusted payment, estimated rate, effective date, alternatives, and counselor information
- Best exam move
- The long initial window generally gives seven to eight months of advance warning for a covered ARM.
- Topic
- Read later notices
- What to know
- Section 1026.20(c), later adjustment, 60 days, 120 days, new rate, new payment, effective date, current index, margin, explanation, and exceptions
- Best exam move
- Do not use the initial 210-to-240-day window for every later adjustment.
- Topic
- Handle index replacement
- What to know
- Unavailable index, unrepresentative index, replacement event, recommended replacement, replacement margin, comparable cost, notice, good faith, contract, and law
- Best exam move
- The creditor cannot simply choose any benchmark; apply the note's replacement procedure and current law.
- Topic
- Assess payment shock
- What to know
- Maximum rate, maximum payment, escrow, interest-only expiration, negative amortization, recast, refinance risk, income change, budget, and foreclosure risk
- Best exam move
- Test affordability at the contractual maximum, not only at the attractive initial payment.
Which distinctions produce the most mistakes?
- Terms
- ARM vs. fixed-rate mortgage
- Difference
- An ARM rate may change under future formula terms. A fixed-rate mortgage keeps the contractual interest rate unchanged, though escrow and total payment can still change.
- Question cue
- Variable note rate versus stable note rate.
- Terms
- ARM vs. step-rate loan
- Difference
- An ARM uses future rates not known at closing because they depend on an index or formula. A step-rate loan has future rates and periods known at closing.
- Question cue
- Unknown indexed changes versus preset changes.
- Terms
- Index vs. margin
- Difference
- The index is the changing external benchmark. The margin is the contractual spread added to it.
- Question cue
- Market component versus lender-set component.
- Terms
- Initial rate vs. fully indexed rate
- Difference
- Initial rate applies at the start and may be discounted. Fully indexed rate is index plus margin before applicable caps and rounding.
- Question cue
- Start rate versus formula rate.
- Terms
- Adjustment date vs. payment-change date
- Difference
- The rate changes on the contractual change date. The payment reflecting that rate is due on the related later date stated by the documents.
- Question cue
- Rate event versus payment event.
- Terms
- Initial cap vs. subsequent cap
- Difference
- Initial cap limits the first adjustment from the starting rate. Subsequent cap limits each later adjustment from the prior rate.
- Question cue
- First reset boundary versus recurring boundary.
- Terms
- Periodic cap vs. lifetime cap
- Difference
- Periodic cap limits one change. Lifetime cap limits the rate over the entire loan.
- Question cue
- One-step ceiling versus overall ceiling.
- Terms
- Cap vs. floor
- Difference
- A cap limits upward or periodic movement as stated. A floor sets a minimum rate or downward boundary.
- Question cue
- Upper or change limit versus lower limit.
- Terms
- Rate cap vs. payment cap
- Difference
- A rate cap limits the interest rate. A payment cap limits payment movement and may fail to cover all interest in some structures.
- Question cue
- Price-of-credit limit versus cash-payment limit.
- Terms
- Interest-only ARM vs. negative-amortization ARM
- Difference
- A full interest-only payment keeps principal level. A payment below accrued interest can add unpaid interest to principal and grow the balance.
- Question cue
- Level balance versus growing balance.
- Terms
- Program disclosure vs. adjustment notice
- Difference
- Program disclosure explains an ARM offering before consummation. Adjustment notice reports an upcoming contractual change after consummation.
- Question cue
- Shopping-stage explanation versus servicing-stage update.
- Terms
- Conversion vs. refinance
- Difference
- A conversion option changes the existing ARM to fixed terms under its clause. Refinancing pays off the ARM with a new loan.
- Question cue
- Contract option versus replacement debt.
The A-D-J-U-S-T ARM calculation
- Agreement: read the note, rider, program disclosure, AIR table, index source, lookback, change dates, rounding, caps, floor, and replacement terms.
- Date: decide whether this is the first adjustment or a later one and identify the applicable current index date.
- Join: add the current index and contractual margin to find the preliminary fully indexed rate.
- Use rounding: follow the contract's exact rounding increment and sequence.
- Set limits: apply initial or subsequent cap, lifetime maximum, minimum rate, and any downward limit.
- Translate to payment: use unpaid principal, final adjusted rate, remaining amortization, and maturity to calculate the new P&I payment.
- Tell the borrower: apply the correct Regulation Z notice timing and contents, then distinguish P&I from total payment.
- Term
- Index
- What it does
- Supplies changing market benchmark
- Common exam mistake
- Treating it as fixed margin
- Term
- Margin
- What it does
- Adds contractual spread
- Common exam mistake
- Assuming it moves every month
- Term
- Rounding
- What it does
- Converts raw sum to allowed increment
- Common exam mistake
- Rounding without instructions
- Term
- Initial cap
- What it does
- Limits first reset
- Common exam mistake
- Using later cap first
- Term
- Subsequent cap
- What it does
- Limits later reset from prior rate
- Common exam mistake
- Measuring only from start rate
- Term
- Lifetime cap or floor
- What it does
- Sets overall upper or lower boundary
- Common exam mistake
- Ignoring it after periodic cap
How do the rules work in scenarios?
Uncapped fully indexed rate
Scenario: The current index is 4.80% and the note margin is 2.25%. The question does not state rounding or a binding cap.
- Add the index and margin.
- 4.80% + 2.25% = 7.05%.
- Do not compare with the initial rate until a cap rule is supplied.
Answer: The preliminary fully indexed rate is 7.05%.
Initial cap binds
Scenario: An ARM starts at 4.50%. At the first change, index plus margin is 7.25%, but the initial adjustment cap is 2 percentage points upward.
- The formula candidate is 7.25%.
- The first-change maximum is 4.50% + 2.00%, or 6.50%.
- The cap prevents the full formula increase at this change.
Answer: The adjusted rate is limited to 6.50%, subject to any other stated limit.
Subsequent cap binds
Scenario: The prior adjusted rate is 6.50%. Index plus margin now equals 8.00%, and the subsequent adjustment cap is 1 percentage point.
- The candidate rate exceeds the prior rate by 1.50 points.
- The later cap permits only a 1.00-point increase from 6.50%.
- The maximum for this adjustment is therefore 7.50%.
Answer: The new rate is limited to 7.50%, subject to lifetime limits.
Lifetime cap overrides the step
Scenario: The periodic cap would permit 9.75%, but the note's lifetime maximum is 9.50%.
- Passing the periodic cap does not end the analysis.
- The lifetime maximum is the overall ceiling.
- The lower permitted ceiling controls.
Answer: The rate cannot exceed 9.50% under the stated terms.
Floor prevents full decrease
Scenario: Index plus margin is 2.75%, but the contract states a 3.25% minimum interest rate.
- The raw formula result is below the contractual floor.
- A downward market move cannot push the rate below 3.25%.
- Any other adjustment limits still need review.
Answer: The stated floor holds the rate at 3.25%.
A flat index can still cause a jump
Scenario: The initial teaser rate is 3.00%. The index remains 2.00%, the margin is 2.50%, and no binding cap changes the result at first reset.
- The fully indexed rate is 2.00% + 2.50%, or 4.50%.
- The index did not rise, but the introductory discount ended.
- The contractual rate therefore moves toward the formula rate.
Answer: The rate can rise to 4.50% even with an unchanged index.
Decode a 5/6m ARM
Scenario: A Loan Estimate identifies the product as a 5/6m Adjustable Rate loan.
- The initial rate generally lasts 5 years.
- After that initial period, the rate may change every 6 months.
- The AIR table and note confirm exact first and later change dates.
Answer: Five-year initial period, then possible six-month adjustments.
What are the common exam traps?
- Trap
- Saying an ARM rate always rises
- Correction
- It can rise, fall, or stay level, subject to the index, margin, caps, floor, and contract.
- Trap
- Treating 5/1 as a five-year term
- Correction
- It usually describes initial-rate duration and later annual adjustments, not total loan maturity.
- Trap
- Adding the initial rate to the index
- Correction
- The basic formula is current index plus margin, not index plus starting rate.
- Trap
- Calling margin the changing benchmark
- Correction
- The index generally moves; the contractual margin generally stays set except under valid replacement terms.
- Trap
- Ignoring the lookback date
- Correction
- Use the index value the contract identifies before the change date, not automatically today's value.
- Trap
- Rounding from habit
- Correction
- Apply only the rounding increment and sequence stated by the note or question.
- Trap
- Using the subsequent cap at first reset
- Correction
- The initial adjustment cap applies first unless the documents expressly provide otherwise.
- Trap
- Measuring every later cap from the initial rate
- Correction
- A subsequent cap commonly measures change from the prior adjusted rate.
- Trap
- Stopping after the periodic cap
- Correction
- Also apply the lifetime maximum, floor, and other contractual limits.
- Trap
- Calling a rate cap a payment cap
- Correction
- A rate cap limits interest rate movement; a payment cap limits payment movement.
- Trap
- Assuming a lower index guarantees lower payment
- Correction
- The floor, prior caps, payment rules, escrow, and other features can prevent or offset a reduction.
- Trap
- Assuming a flat index prevents payment shock
- Correction
- A teaser rate or expiring interest-only feature can cause a payment increase even with a flat index.
- Trap
- Using original principal for a reset payment
- Correction
- A normally amortizing ARM payment is recalculated from unpaid principal and remaining term.
- Trap
- Using one notice window for every adjustment
- Correction
- Initial and later Regulation Z adjustment notices generally use different advance periods.
- Trap
- Treating the product label as the whole contract
- Correction
- Confirm exact index, margin, dates, caps, floor, rounding, payment terms, and replacement rules in the documents.
Can you answer these original practice questions?
These questions are original study items aligned to the published outline. They are not copied, recalled, or predicted PSI questions.
1. What is the basic ARM rate formula before caps and rounding?
- Index plus margin
- Initial rate plus principal
- APR plus escrow
- Margin minus maturity
Show answer and explanation
Answer: Index plus margin
The current index supplies the changing component, and the margin supplies the contractual spread.
2. What does 5/1 generally mean in a hybrid ARM label?
- Fixed initial rate for 5 years, then possible annual adjustments
- A five-year loan with one payment
- Five indexes and one margin
- Five percent interest for one month
Show answer and explanation
Answer: Fixed initial rate for 5 years, then possible annual adjustments
The first number is the initial period and the second is the later adjustment frequency.
3. The index is 4.25% and margin is 2.50%. What is the raw fully indexed rate?
- 1.75%
- 4.25%
- 6.75%
- 10.625%
Show answer and explanation
Answer: 6.75%
Add 4.25% and 2.50% before applying stated caps, floor, and rounding.
4. An ARM starts at 4%. The uncapped first-reset rate is 7%, and the initial upward cap is 2 points. What is the highest first-reset rate under these facts?
- 4%
- 6%
- 7%
- 9%
Show answer and explanation
Answer: 6%
The first-change cap limits movement from 4% to 6%, even though the formula produces 7%.
5. What does a lifetime cap do?
- Limits the rate over the entire loan
- Limits only the first payment
- Fixes property taxes
- Eliminates the index
Show answer and explanation
Answer: Limits the rate over the entire loan
It provides an overall boundary beyond the initial and later periodic caps.
6. Can a teaser-rate ARM rise if the index is unchanged?
- Yes, when the initial discount ends and the formula rate is higher
- No, never
- Only when taxes fall
- Only after maturity
Show answer and explanation
Answer: Yes, when the initial discount ends and the formula rate is higher
The initial rate can be below index plus margin, so expiration of the discount can produce an increase.
7. What is the key difference between an index and a margin?
- The index generally changes; the contractual margin generally stays set
- The margin is market value
- The index is the down payment
- They are always identical
Show answer and explanation
Answer: The index generally changes; the contractual margin generally stays set
Together they create the preliminary formula rate under the loan terms.
8. For a covered ARM, what is the general federal window for the initial adjustment notice?
- 210 to 240 days before the first adjusted payment is due
- Exactly 10 days after payment
- Only at foreclosure
- No advance notice
Show answer and explanation
Answer: 210 to 240 days before the first adjusted payment is due
Section 1026.20(d) uses that general window, with a consummation rule when the first adjusted payment arrives sooner.
9. Which disclosure table summarizes an ARM's index, margin, and rate-change limits?
- The Adjustable Interest Rate table
- The deed acknowledgment
- The property tax bill
- The brokerage ledger
Show answer and explanation
Answer: The Adjustable Interest Rate table
The AIR table on the Loan Estimate or Closing Disclosure organizes the adjustable-rate formula and limits.
10. What is safest when calculating a new ARM payment?
- Use unpaid principal, final adjusted rate, and remaining term under the note
- Always use original principal
- Use market value as principal
- Ignore caps
Show answer and explanation
Answer: Use unpaid principal, final adjusted rate, and remaining term under the note
A standard amortizing ARM recalculates the payment needed to retire the current balance by maturity at the adjusted rate.
How should you study this area?
- Session
- Session 1
- Focus
- Decode ARM labels
- Proof you are ready
- Translate 30 product labels, including 3/1, 5/1, 7/1, 10/1, and 5/6m, into initial and later adjustment timelines.
- Session
- Session 2
- Focus
- Calculate formula rates
- Proof you are ready
- Complete 30 index-plus-margin calculations using only the stated lookback and rounding rule.
- Session
- Session 3
- Focus
- Apply every limit
- Proof you are ready
- Resolve 30 first, subsequent, lifetime, floor, and falling-index cases and show which boundary controls.
- Session
- Session 4
- Focus
- Recalculate payment
- Proof you are ready
- Use unpaid balance, adjusted rate, and remaining term in 20 payment scenarios, separating P&I from escrow and total payment.
- Session
- Session 5
- Focus
- Read disclosures and notices
- Proof you are ready
- Annotate the CHARM booklet, two AIR tables, one program disclosure, and both initial and later section 1026.20 notice models.
- Session
- Session 6
- Focus
- Run A-D-J-U-S-T
- Proof you are ready
- Audit two complete ARM files, calculate three resets, test payment shock, score at least 90 percent, and explain every miss.
Do not count recognition as mastery. Close the notes and explain the rule, apply it to a new fact pattern, and identify why each distractor fails.
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Questions students ask about Adjustable-Rate Mortgage: Illinois Exam Guide
What is an adjustable-rate mortgage?
An adjustable-rate mortgage, or ARM, is a mortgage whose interest rate can change after consummation under a formula and timing stated in the loan documents. Many ARMs begin with a fixed initial rate, then adjust using a published index plus a margin, subject to contractual caps, floors, rounding rules, and change dates.
What do the two numbers in a 5/1 or 5/6m ARM mean?
The first number generally tells how many years the initial rate lasts. The second tells how often the rate may adjust afterward. A 5/1 ARM is initially fixed for 5 years and then may adjust every year. A 5/6m ARM is initially fixed for 5 years and then may adjust every 6 months. Read the actual note because product labels summarize rather than replace terms.
What is the index on an ARM?
The index is an external benchmark that moves with market conditions and is identified in the loan terms. Current Fannie Mae and Freddie Mac standard ARM instruments use the 30-day Average SOFR published by the Federal Reserve Bank of New York, but other ARM programs may use another lawful index. The contract states the source, lookback, and replacement procedure.
What is the margin on an ARM?
The margin is the percentage added to the current index to calculate the fully indexed rate before caps, floors, and rounding. It is set in the loan agreement. The index may move over time, while the original margin usually remains fixed unless a valid replacement-index provision also permits a replacement margin.
How is an adjusted ARM rate calculated?
Start with the contract's current index value, add the margin, apply the required rounding method, then apply the initial, periodic, lifetime, and minimum-rate limits in the order the note requires. For example, a 4.80% index plus a 2.25% margin produces 7.05% before rounding and caps. The note controls the final rate.
What are initial, subsequent, and lifetime ARM caps?
The initial cap limits the first adjustment from the initial rate. The subsequent cap limits change from the prior rate at later adjustments. The lifetime cap limits total movement over the loan's life, commonly by reference to the initial rate. A floor can limit downward movement. Cap notation must be read with the product documents, not guessed.
Can an ARM payment change even if the index does not?
Yes. If an initial discounted or teaser rate is below the fully indexed rate, the rate and payment can rise at the first change even if the index is unchanged. Payment can also change when an interest-only period ends, amortization is recalculated, escrow changes, mortgage insurance changes, or another contractual feature takes effect.
Does an ARM rate always rise?
No. Depending on the index movement and contract, it may rise, fall, or remain unchanged. Caps limit increases or decreases, and a floor can prevent the rate from falling below a stated level. The margin can function as a practical minimum in some structures, but students should read the stated minimum-rate clause.
When must the first ARM adjustment notice be sent?
For an ARM covered by Regulation Z section 1026.20(d), the separate initial adjustment disclosure generally must be provided at least 210 but no more than 240 days before the first payment at the adjusted level is due. If that payment is due within the first 210 days after consummation, the disclosure is provided at consummation. Coverage and exceptions must be checked.
When are later ARM adjustment notices sent?
For adjustments covered by section 1026.20(c), the notice generally must be provided at least 60 but no more than 120 days before the first payment at the adjusted level is due. The regulation contains coverage rules, timing variations, and exceptions, so the exact loan and current text control.
Are these official PSI questions or mortgage advice?
No. The questions are original, and primary sources were checked through August 1, 2026. This is exam education, not lending, refinancing, servicing, investment, or legal advice. A live ARM analysis requires the note, rider, program disclosure, Loan Estimate, Closing Disclosure, index publication, notices, payment history, and current applicable law.
Primary sources
- PSI Illinois Candidate Information Booklet effective June 24, 2026
- Consumer Financial Protection Bureau, current fixed-rate versus adjustable-rate mortgage guidance updated May 2026
- Consumer Financial Protection Bureau, official ARM index and margin explanation
- Consumer Financial Protection Bureau, official initial, subsequent, and lifetime ARM cap explanation
- Consumer Financial Protection Bureau, current Consumer Handbook on Adjustable Rate Mortgages
- Consumer Financial Protection Bureau, current Regulation Z section 1026.19 ARM program disclosures
- Consumer Financial Protection Bureau, current Regulation Z section 1026.20 adjustment notices and official interpretations
- Consumer Financial Protection Bureau, current Regulation Z section 1026.37 Loan Estimate and AIR table rules
- Fannie Mae/Freddie Mac Multistate Adjustable Rate Note Form 3441 using 30-day Average SOFR
- Fannie Mae current legal-document library for fixed, adjustable, and fixed-adjustable uniform instruments
The current official outline controls the tested scope. Statutes, regulations, and official agency materials control when a general study rule and a jurisdiction-specific rule differ.
Editorial status
Checked against primary sources
The Pass Illinois editorial team last checked this guide on August 1, 2026. Every practice question is an original study item, and the source links above let you verify the rules that support the lesson.