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66 practical guidesRetirement · Investing · Taxes · Savings · Debt · Housing · Family · Protection

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MFA puts the useful guides in an order, then connects each one to the tool that lets you run the numbers.

Six practical starting paths

Curated MFA learning path

Build your retirement system

Understand the workplace plan, capture the match, know the limits, choose tax treatment and connect contributions to an actual retirement target.

Where this gets youFinish with the pieces needed to turn a 401(k) from a benefit you have into a plan you understand.

6 guidesAbout 44 min total0/6 completedEvery step connects to an MFA tool

1Retirement · 7 minWhat Is a 401(k)? How Contributions, Matches and Limits Work

A 401(k) is more than a payroll deduction. Understand employee contributions, employer matches, current limits, vesting and the decisions that actually matter.

Then run: 401(k) Match Calculator →2Retirement · 7 minHow a 401(k) Employer Match Actually Works

Translate a 401(k) match formula into real employee and employer dollars and understand why contribution rate, eligible pay and plan rules matter.

Then run: 401(k) Match Calculator →3Retirement · 8 min401(k) Contribution Limits: Employee, Match and Total Plan Rules

Understand how annual 401(k) employee deferral limits, catch-up contributions, employer dollars and the overall plan limit fit together without double-counting the buckets.

Then run: 401(k) Contribution Calculator →4Retirement · 7 minRoth vs Traditional 401(k): When You Pay Taxes Changes

Traditional and Roth 401(k) contributions use different tax timing. Compare the current paycheck cost, future tax assumptions and the trade-offs that matter.

Then run: Roth vs Traditional Calculator →5Retirement · 8 minHow Much Should I Save for Retirement? Build a Target From Your Numbers

Estimate retirement saving needs from your age, current balance, target retirement date, spending goal and contribution path instead of relying on one flat percentage rule.

Then run: Retirement Goal Calculator →6Retirement · 7 minRoth Conversion Basics: Paying Tax Now to Change Future Tax Treatment

A Roth conversion moves eligible retirement dollars into Roth treatment and can generate taxable income today. Learn how conversions differ from contributions, why IRA basis matters and what to model before acting.

Then run: Roth vs Traditional Calculator →

Continue hereWhat Is a 401(k)? How Contributions, Matches and Limits Work

Continue path

New in MFA Guides

Eight new decision guides.

Fresh practical guides on mortgages, debt, retirement plans, health insurance, withholding and family planning.

15-Year vs 30-Year MortgageNew guide

Required payment, lifetime interest and repayment flexibility

Read guide FHA vs Conventional MortgageNew guide

Down payment, mortgage insurance and quote-by-quote cost

Read guide Seller Credits vs Mortgage PointsNew guide

Separate seller credits, lender credits, points and cash to close

Read guide 0% Balance Transfer Credit CardsNew guide

Transfer fee, promotional APR and the payoff deadline

Read guide 401(k) Loan vs Hardship WithdrawalNew guide

Repayment, taxes, job-change risk and retirement opportunity cost

Read guide PPO vs HMO Health InsuranceNew guide

Network access, referrals and annual cost compared

Read guide How Form W-4 Withholding WorksNew guide

Federal income-tax withholding, paychecks and year-end tax

Read guide Prenup BasicsNew guide

Financial disclosure, property questions and state-law planning

Read guide

Browse by topic

Six broader money hubs.

Use a topic hub when you want the surrounding concepts and tools, not just one article.

Retirement15 Guides

Learn 401(k)s, IRAs, Roth decisions, rollovers, Social Security, RMDs and retirement tax mechanics with plain-English MFA guides and connected calculators.

Open topic Home & Mortgage12 Guides

Understand affordability, fixed vs ARM loans, PMI, closing costs, points, refinancing, prepayment, rent vs buy and home-equity borrowing with MFA guides and calculators.

Open topic Investing & Taxes13 Guides

Learn ETFs, index funds, asset allocation, fees, compounding, capital gains, tax-loss harvesting, RSUs and ESPPs with MFA guides and interactive planning tools.

Open topic Saving & Debt16 Guides

Learn budgeting, emergency funds, APY, HYSA and CDs, money market funds, credit scores, utilization, card interest and debt payoff with MFA guides and calculators.

Open topic Family & Protection12 Guides

Learn beneficiaries, life insurance, health-plan costs, HSA/FSA rules, 529s, custodial accounts, umbrella insurance, wills and trusts with MFA guides and planning tools.

Open topic Tax & Paycheck12 Guides

Learn marginal versus effective tax rates, Roth versus Traditional tax timing, capital gains, RSUs, ESPPs, Roth conversions and Medicare IRMAA with MFA guides and calculators.

Open topic

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66 guides

Retirement7 min

What Is a 401(k)? How Contributions, Matches and Limits Work

A 401(k) is more than a payroll deduction. Understand employee contributions, employer matches, current limits, vesting and the decisions that actually matter.

Then run it401(k) Match Calculator

Retirement7 min

Roth vs Traditional 401(k): When You Pay Taxes Changes

Traditional and Roth 401(k) contributions use different tax timing. Compare the current paycheck cost, future tax assumptions and the trade-offs that matter.

Then run itRoth vs Traditional Calculator

Investing7 min

What Is an ETF? A Plain-English Guide to the Fund Wrapper

An ETF is a fund that trades on an exchange. Learn what the wrapper does, what can be inside it, what costs matter and why ETF does not automatically mean diversified.

Then run itCompound Growth Calculator

Investing7 min

Index Funds vs Individual Stocks: The Real Trade-Offs

Broad index funds and individual stocks solve different problems. Compare diversification, concentration, effort, cost and the role each can play in a portfolio.

Then run itCompound Growth Calculator

Estate & family6 min

Why Beneficiary Designations Matter

Beneficiary forms can control who receives certain retirement accounts, insurance proceeds and other assets. Learn what to review, when to update them and where estate planning still matters.

Then run itKids & Family

Money basics7 min

How to Build a Budget You Can Actually Use

A useful budget is a decision system, not a punishment. Start with take-home pay, fixed obligations, flexible spending and monthly room for the goals that matter.

Then run itBudget Calculator

Savings7 min

How Much Emergency Fund Do You Need?

Build an emergency-fund target from essential monthly spending, household risk and liquidity needs instead of relying on one universal rule.

Then run itEmergency Fund Calculator

Savings6 min

High-Yield Savings Account vs CD: Which Fits the Goal?

Compare high-yield savings and CDs by access, rate structure, term, penalties and the actual dollars your balance may earn.

Then run itSavings & CD Rates

Savings5 min

How APY Works: Rate, Compounding and Dollar Interest

Understand APY, compounding, variable and promotional rates, and how to turn a headline percentage into estimated interest dollars.

Then run itSavings & CD Rates

Debt7 min

Debt Snowball vs Avalanche: Which Payoff Method Does What?

Compare debt snowball and avalanche with the same payment budget so you can see the real trade-off between interest efficiency and early wins.

Then run itDebt Snowball vs Avalanche

Debt7 min

How Credit Card Interest Works — and Why Minimum Payments Matter

Understand how APR, revolving balances and monthly payments affect credit-card interest and why increasing the payment can change payoff time dramatically.

Then run itCredit Card Payoff Calculator

Debt8 min

Pay Off Debt or Invest? Compare the Trade-Offs Correctly

Compare contractual debt interest with uncertain market returns without overlooking employer matches, emergency cash, taxes, liquidity and time horizon.

Then run itNext Dollar

Housing8 min

How Much House Can I Afford? A Practical Framework

Estimate affordability from income, debts, down payment, ownership costs and post-closing reserves instead of treating a lender maximum as your budget.

Then run itHome Affordability Calculator

Housing8 min

Rent vs Buy a Home: What the Math Should Include

Compare renting and buying using the full cash-flow and wealth picture, including transaction costs, maintenance, equity, appreciation and time horizon.

Then run itRent vs Buy Calculator

Housing7 min

When Does Refinancing a Mortgage Make Sense?

Evaluate refinancing with break-even time, closing costs, remaining term and total modeled interest instead of relying on a rate-drop rule of thumb.

Then run itRefinance Calculator

Housing8 min

Extra Mortgage Payments vs Investing: How to Compare

Compare mortgage interest saved with uncertain investment outcomes while keeping liquidity, taxes, time horizon and other financial priorities visible.

Then run itMortgage Prepayment Calculator

Retirement7 min

How a 401(k) Employer Match Actually Works

Translate a 401(k) match formula into real employee and employer dollars and understand why contribution rate, eligible pay and plan rules matter.

Then run it401(k) Match Calculator

Retirement8 min

What Happens to Your 401(k) When You Leave a Job?

Understand the common options for an old 401(k), how direct rollovers work and which tax, fee and planning issues deserve review before moving the money.

Then run itRetirement Calculators

Family7 min

529 Plan Basics: How College Savings Accounts Work

Learn how 529 plans work, what qualified education spending means, how state features differ and where a college goal fits within the rest of a family plan.

Then run it529 College Savings Calculator

Insurance8 min

How Much Life Insurance Do I Need? Build the Coverage Gap

Estimate life-insurance need from survivor support, debts, education goals, existing coverage and available assets rather than relying on a single salary multiple.

Then run itLife Insurance Needs Calculator

Retirement8 min

401(k) Contribution Limits: Employee, Match and Total Plan Rules

Understand how annual 401(k) employee deferral limits, catch-up contributions, employer dollars and the overall plan limit fit together without double-counting the buckets.

Then run it401(k) Contribution Calculator

Retirement9 min

Backdoor Roth IRA: How the Two-Step Strategy Works

Learn how nondeductible Traditional IRA contributions and Roth conversions work together, why Form 8606 matters and how the pro-rata rule can change the tax result.

Then run itRoth vs Traditional Calculator

Retirement9 min

Mega Backdoor Roth: After-Tax 401(k) Contributions Explained

Understand when an employer plan can support a mega backdoor Roth, how after-tax contributions use the overall plan limit and why conversion mechanics matter.

Then run it401(k) Contribution Calculator

Retirement8 min

How Much Should I Save for Retirement? Build a Target From Your Numbers

Estimate retirement saving needs from your age, current balance, target retirement date, spending goal and contribution path instead of relying on one flat percentage rule.

Then run itRetirement Goal Calculator

Building wealth7 min

What Is Net Worth? Assets Minus Debts, Explained Clearly

Learn what belongs in net worth, why income and net worth are different, and how tracking assets, liabilities and liquidity can improve financial decisions.

Then run itNet Worth Calculator

Health care8 min

HSA vs FSA: Eligibility, Ownership, Taxes and Carryover

Compare HSAs and health FSAs across eligibility, ownership, tax treatment, unused balances and employer-plan rules before choosing how to fund medical expenses.

Then run itHealth Care Costs

Health care8 min

Deductible vs Coinsurance vs Out-of-Pocket Max

Understand how deductibles, coinsurance and out-of-pocket maximums work together so you can compare health plans using total annual cost instead of premium alone.

Then run itHealth Care Costs

Insurance9 min

Term vs Whole Life Insurance: Start With the Coverage Need

Compare term and whole life insurance by coverage duration, cash value, cost structure and guarantees after first defining the financial risk your household needs to insure.

Then run itLife Insurance Needs Calculator

Family8 min

529 vs UGMA/UTMA: College Savings vs Custodial Accounts

Compare 529 plans with UGMA and UTMA custodial accounts across ownership, taxes, education restrictions, control and the long-term purpose of the money.

Then run it529 College Savings Calculator

Cards & rewards8 min

Is a Credit Card Annual Fee Worth It? Run the Break-Even Math

Evaluate a credit-card annual fee using rewards you actually earn, benefits you truly use, point-value assumptions and any incremental membership costs.

Then run itCards & Rewards

Investing7 min

ETF vs Mutual Fund: What Actually Changes?

ETFs and mutual funds can own nearly identical portfolios. The important differences are how you trade them, how they are priced, potential tax mechanics, fees and how well the wrapper fits the account you are using.

Then run itCompound Growth Calculator

Investing7 min

Investment Fees and Expense Ratios: The Cost You Don't See as a Bill

A 0.20% fee can look tiny, but costs compound over decades. Learn what an expense ratio covers, what it does not cover, and how to compare investment costs in actual dollars.

Then run itCompound Growth Calculator

Investing7 min

Asset Allocation and Rebalancing: Keep Risk From Drifting by Accident

Your portfolio mix can change even when you do nothing. Learn how asset allocation, diversification and rebalancing work together, and how to distinguish a deliberate risk decision from performance chasing.

Then run itRetirement Goal Calculator

Taxes7 min

Short-Term vs Long-Term Capital Gains: Why the Holding Period Matters

Federal tax rules generally separate capital gains and losses by whether an asset was held for more than one year. Learn the holding-period distinction, basis, netting and why your final tax result is broader than one headline rate.

Then run itTake-Home Pay Calculator

Taxes7 min

Tax-Loss Harvesting Basics: The Tax Benefit Is Not the Investment Plan

Realized investment losses can offset gains, but the wash-sale rule and replacement investment matter. Learn the mechanics before turning a tax idea into unnecessary portfolio churn.

Then run itMoney Plan

Retirement7 min

Roth Conversion Basics: Paying Tax Now to Change Future Tax Treatment

Then run itRoth vs Traditional Calculator

Retirement8 min

Solo 401(k) vs SEP IRA: A Practical Self-Employed Retirement Comparison

Solo 401(k)s and SEP IRAs can both help business owners save for retirement, but contribution mechanics, employee rules and administration differ. Start with the business facts before chasing a maximum limit.

Then run it401(k) Contribution Calculator

Insurance7 min

Umbrella Insurance Basics: What Extra Liability Coverage Is For

Umbrella insurance can add liability coverage above underlying auto, homeowners or renters policies. Learn what it is designed to protect, why underlying limits matter and how to frame the amount of coverage.

Then run itNet Worth Calculator

Estate & family8 min

Will vs Trust: Different Tools, Different Jobs

A will and a trust can both be part of an estate plan, but they do not do the same job. Learn how probate, asset ownership and beneficiary designations fit together, and why state law matters.

Then run itAdvanced Planning

Housing7 min

Mortgage Points vs Lower Rate: When Paying Upfront Actually Breaks Even

Discount points trade more cash at closing for a lower mortgage rate. The useful question is how long it takes monthly savings to recover the upfront cost—and whether you will keep the loan that long.

Then run itMortgage Decision Lab

Retirement9 min

Social Security at 62 vs 67 vs 70: How to Think About Claiming Age

Claiming Social Security earlier gives you checks sooner but usually reduces the monthly benefit. Delaying can raise the monthly amount, but the right choice depends on longevity, spouse benefits, work, taxes and how the rest of retirement is funded.

Then run itReady to Retire

Retirement9 min

Required Minimum Distributions: What RMDs Actually Require

RMDs force minimum withdrawals from certain tax-deferred retirement accounts after the applicable starting age. Learn the current ages, why account type matters and how RMD income can interact with taxes and Medicare.

Then run itReady to Retire

Retirement9 min

Medicare IRMAA: Why Retirement Income Can Change Your Premium

IRMAA is an income-related surcharge on Medicare Part B and Part D for higher-income beneficiaries. Learn how the lookback works, what 2026 thresholds mean and why Roth conversions or capital gains can affect future premiums.

Then run itReady to Retire

Retirement8 min

Traditional IRA vs Roth IRA: The Tax Timing and Eligibility Trade-Off

Traditional and Roth IRAs share one annual contribution limit but use different tax rules. Compare deductibility, Roth eligibility, tax timing and how each fits with workplace retirement savings.

Then run itRoth vs Traditional Calculator

Insurance8 min

Should You Invest Your HSA? Start With Medical Liquidity

HSAs can combine valuable tax treatment with long-term investing, but medical cash needs come first. Learn when investing HSA dollars can make sense and how deductible, out-of-pocket exposure and emergency savings change the answer.

Then run itHealth Care Costs

Investing9 min

RSU Taxes: Vesting, Withholding and What Happens When You Sell

Restricted stock units are usually taxed as compensation when shares or cash are delivered after vesting, then later share-price changes can create capital gains or losses. Learn the two tax events and why withholding may not equal the final bill.

Then run itTake-Home Pay Calculator

Investing9 min

Employee Stock Purchase Plans: When the Discount Is Worth the Concentration

An ESPP can let employees buy employer stock through payroll deductions, sometimes at a discount or with a lookback. Learn the cash-flow, tax and concentration trade-offs before treating the discount like free money.

Then run itTake-Home Pay Calculator

Money basics7 min

Credit Utilization: What the Percentage Actually Means

Credit utilization compares reported revolving balances with available credit limits. Lower utilization is generally better for common scoring models, but 30% is not a magic cliff and carrying interest is never required just to create a score.

Then run itCredit Card Payoff Calculator

Building wealth8 min

HELOC vs Cash-Out Refinance: Which Debt Are You Actually Repricing?

A HELOC borrows against home equity without replacing the first mortgage, while a cash-out refinance replaces the existing mortgage with a larger new one. Compare rate structure, fees and the amount of debt being repriced.

Then run itRefinance Calculator

Money basics8 min

Treasury Bills vs HYSA vs CDs: Where Short-Term Cash Actually Fits

Treasury bills, high-yield savings accounts and CDs all compete for short-term cash, but they differ in taxes, access, rate certainty and maturity. Compare the after-tax and liquidity trade-offs, not just the headline yield.

Then run itSavings & CD Rates

Money basics9 min

How Credit Scores Work: What Actually Moves the Number

Understand what a credit score measures, why there is no single universal score, which credit-report factors can matter and why carrying interest is not required to build credit.

Then run itCredit Card Payoff Calculator

Building wealth9 min

How Compound Interest Works: Contributions, Time and Growth

See how starting balance, recurring contributions, time and an assumed rate interact, and separate the dollars you contribute from the growth produced by compounding.

Then run itCompound Growth Calculator

Money basics8 min

APR vs APY: Why the Two Percentages Mean Different Things

Understand why APR is commonly used for borrowing cost while APY describes annualized deposit yield with compounding, then translate both into actual dollars.

Then run itCredit Card Payoff Calculator

Money basics9 min

Marginal vs Effective Tax Rate: Why Your Tax Bracket Is Not Your Average Rate

Understand why a marginal tax rate applies to the next dollar in a bracket while an effective rate is an average, and why a higher bracket does not tax all prior income at that rate.

Then run itTake-Home Pay Calculator

Housing10 min

Fixed vs Adjustable-Rate Mortgage: How to Compare the Risk, Not Just the Starting Rate

Compare fixed-rate and adjustable-rate mortgages across initial payment, future reset risk, index and margin mechanics, rate caps and the danger of relying on a future refinance.

Then run itMortgage Decision Lab

Housing9 min

Private Mortgage Insurance (PMI): Cost, LTV and When It Can End

Understand conventional PMI, how loan-to-value changes as principal falls, and the 80% request and scheduled 78% automatic-termination concepts for many eligible loans.

Then run itMortgage Decision Lab

Housing10 min

Mortgage Closing Costs Explained: From Down Payment to Cash to Close

Break cash to close into down payment, lender and title costs, points, prepaids, credits and deposits so you can compare Loan Estimates instead of rate alone.

Then run itClosing Cost Calculator

Money basics9 min

Money Market Fund vs HYSA: Similar Cash Yields, Different Products

Compare money market mutual funds with high-yield savings accounts across yield, liquidity, settlement, FDIC insurance and the important difference between a fund and a bank deposit.

Then run itSavings & CD Rates

Housing8 min

15-Year vs 30-Year Mortgage: The Payment, Interest and Flexibility Trade-Off

A shorter mortgage can reduce lifetime interest, while a longer term can preserve monthly flexibility. Compare actual quoted rates, required payments and what you would do with the difference.

Then run itMortgage Decision Lab

Housing9 min

FHA vs Conventional Mortgage: Compare the Actual Loan, Not the Label

FHA can improve access for some borrowers while conventional financing can cost less for others. Compare down payment, mortgage insurance, rate, cash to close and the full lender quote.

Then run itMortgage Decision Lab

Housing8 min

Seller Credits vs Lender Credits vs Mortgage Points: Do Not Mix the Three

Seller credits, lender credits and discount points can all change cash to close, but they do different things. Separate who funds the credit from the rate trade-off and compare over your holding period.

Then run itMortgage Decision Lab

Debt & credit8 min

0% Balance Transfer Credit Cards: The Payoff Deadline Matters More Than the Headline

A 0% balance transfer can reduce interest, but the transfer fee and promotional deadline matter. Calculate the fee in dollars and the payment needed to finish before the regular APR begins.

Then run itCredit Card Payoff

Retirement9 min

401(k) Loan vs Hardship Withdrawal: Two Very Different Ways to Access Retirement Money

A 401(k) loan creates a repayment obligation while a hardship distribution generally removes retirement money permanently. Compare plan rules, taxes, payroll burden, job-change risk and lost compounding.

Then run itNext Dollar

Insurance8 min

PPO vs HMO Health Insurance: Compare the Network Before the Deductible

PPO and HMO labels mainly describe access and network structure. Compare actual premiums, doctors, hospitals, referrals, out-of-network rules and expected annual cost before choosing.

Then run itHealth Care Costs

Taxes8 min

How Form W-4 Works: Withholding Is a Prepayment, Not Your Tax Bill

Form W-4 affects federal income-tax withholding from paychecks. Understand the difference between withholding and final tax liability, and use the IRS estimator when the household has multiple income sources.

Then run itTake-Home Pay

Family & protection9 min

Prenup Basics: Start With the Financial Conversation Before the Legal Draft

A prenup is a state-law legal agreement, not a generic financial template. Start with a clear inventory of assets, debts, businesses and expectations, then use qualified counsel for the agreement itself.

Then run itAdvanced Planning

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