The MoneyWhatIf handbook
Financial concepts,
made clear.
Understand the terms behind your forecast. Every guide starts with a simple explanation, walks through an example, and shows how the calculation works in MoneyWhatIf.
57 guides
Reading the forecast
Understand chart scales, purchasing power, and the range of possible outcomes.
5 guides
Today’s money and inflation adjustment
Translate future dollar amounts into today’s purchasing power, making values across different years easier to compare.
2 min readLogarithmic chart scale
Keep smaller values readable beside very large ones. A logarithmic-style scale changes the chart’s shape while preserving its dollar amounts.
2 min readTaxable net worth
Estimate what could remain after tax if assets were sold or withdrawn in the same year. This is a hypothetical view of your net worth.
2 min readSequence-of-returns risk
The order of market gains and losses matters, especially when you are withdrawing money. Explore why early losses can have lasting effects.
2 min readPlan Resilience and repeated market paths
Test your full plan against reshuffled historical returns and see how often it covers every year’s spending under those assumptions.
3 min readPlan simulators
Explore historical markets and spending that responds to your portfolio.
2 guides
Market Simulator and historical returns
Replay an index’s historical annual returns through selected accounts. Choose when that market history begins in your plan.
3 min readSpending Simulator and dynamic retirement spending
Explore retirement spending that responds to your portfolio, within the floor, ceiling, and flexibility settings you choose.
3 min readHousehold & cash flow
Plan life events, family costs, debt payments, and what happens to extra cash.
7 guides
Give every extra dollar a job
Keep a cash cushion, fund an account, pay down debt, and invest what remains—in the order you choose.
2 min readStart a plan partway through the year
Combine today’s balances with the months still ahead. The first year’s tax is worked out on the whole calendar year, from the plan’s own incomes unless you enter the real figures.
2 min readLet a milestone set the date
Define a financial milestone, see when it happens, and use it to time retirement or another plan entry.
2 min readSchedule income and spending over time
Use date ranges, inflation adjustments, and custom curves to describe how an amount changes through your life.
2 min readPlan for children and education costs
Build age-based budgets for each child and name the accounts that should pay for education.
2 min readModel loans and extra repayments
Set a loan balance, interest rate, and payment plan, then explore paying it down before investing extra cash.
2 min readPlan for both lifetimes
Understand how ownership, separate retirement dates, and lifespans affect the surviving household’s income, taxes, and accounts.
2 min readIncome & investing
Set up pensions, stock grants, investment returns, dividends, fees, and bonds.
4 guides
Model a pension from work to retirement
Separate what a pension takes from your paycheck from the benefit it later pays, including inflation adjustments and survivor income.
2 min readTurn stock grants into a vesting forecast
Model existing unvested stock, future refresh grants, the tax at vesting, and how much stock you keep.
2 min readSeparate growth, dividends, and fees
Understand which assumptions an account inherits, which it overrides, and why the same return can produce different after-tax results.
2 min readAdd bonds and change your investment mix
Set an account’s bond share over time and split it between bond types.
2 min readTaxes
Learn how income, gains, and deductions affect the modeled tax bill.
15 guides
Progressive tax brackets
Higher tax rates apply to the income within each bracket. Learn the difference between your marginal rate and your overall tax rate.
2 min readFederal and state itemized deductions
Eligible expenses can reduce taxable income. See how the model compares itemized deductions with the standard deduction under federal and state rules.
4 min readModified adjusted gross income (MAGI)
Modified adjusted gross income helps determine certain taxes, benefits, and contribution limits. Its definition depends on the rule using it.
2 min readNet investment income tax (NIIT)
Understand the additional 3.8% federal tax that can apply to investment income when income exceeds a threshold.
2 min readCapital gains and cost basis
When you sell an asset, its cost basis helps determine the taxable gain. See how MoneyWhatIf tracks basis and models gains and losses.
2 min readPayroll and self-employment taxes
Social Security and Medicare taxes are calculated separately from income tax. See how wages and self-employment income are treated.
2 min readLocal income tax
Some cities, counties, and school districts charge income tax. Learn how supported local rules affect working and retirement years.
3 min readMarried filing separately
See how the model calculates separate tax returns for a married couple, including each person’s income, deductions, and surcharges.
4 min readCanada, the UK and Australia
Explore the model’s Canadian, UK, and Australian tax rules, retirement accounts, and government benefits by choosing a country under Household.
5 min readSeparate the tax year from the payment year
Choose whether tax is paid as it arises or partly settled the following year, and see the effect on available cash.
2 min readUnderstand the alternative minimum tax
See why a parallel federal calculation can add tax beyond the ordinary brackets.
2 min readUse carried capital losses in the forecast
Enter losses from before the plan and follow how losses realized during the forecast offset later gains.
2 min readRealize gains while keeping the money invested
Use Tax Planning to test realizing selected brokerage gains now, raising basis for later withdrawals.
2 min readFund charitable giving from an IRA
Declare giving already in your budget and let eligible IRA distributions fund it without counting the same gift twice.
2 min readCompare a move to another state
Set a future residence and see how a move changes modeled state and local taxes from that year onward.
2 min readBenefits & health coverage
Plan for retirement benefits, health coverage, and care costs.
6 guides
Social Security retirement benefits and claiming age
Explore how your benefit estimate, future earnings, and claiming date affect the Social Security income in your forecast.
3 min readTaxation of Social Security benefits
Other income can make part of your Social Security benefit taxable. Learn what the 50% and 85% inclusion limits mean.
2 min readMedicare Parts B and D premiums
See how the forecast estimates Medicare premiums from age 65, before supplemental coverage and income-related surcharges.
3 min readMedicare IRMAA surcharges
Higher income can raise Medicare premiums later. Learn how income tiers and the two-year lookback affect the forecast.
2 min readLong-term care and the medical deduction
Plan for paid care at home or in a care facility. Explore timing, duration, insurance benefits, and the model’s medical-expense deduction.
4 min readPrice health coverage before Medicare
Enter marketplace premiums and household size, then see how income affects the premium credit and its later reconciliation.
2 min readAccounts & withdrawals
Understand contributions, conversions, and the rules for taking money out.
10 guides
Contribution limits and phaseouts
See how contribution ceilings, age, compensation, income, and available cash limit the amount your plan can save.
4 min readHow Roth conversions work
Move money from a pre-tax retirement account into Roth. See how the tax cost today can change future withdrawals and required distributions.
3 min readRequired minimum distributions (RMDs)
Required withdrawals from eligible retirement accounts. Learn when the model starts them, how it calculates the amount, and where the money goes.
2 min readWithdrawal order and the funding waterfall
Choose which accounts or properties the plan draws from when income and cash cannot cover the year’s spending.
2 min readTax gross-up for withdrawals
A taxable withdrawal may need to cover both your spending and the tax it creates. See how the model calculates the extra amount.
2 min readEarly retirement-account withdrawals
Accessing retirement money early can create taxes or penalties. See how account type, age, and modeled exceptions affect a withdrawal.
2 min readRule 72(t) substantially equal periodic payments
Model a series of equal retirement-account payments that can qualify for an exception to the usual early-withdrawal penalty.
2 min readScheduled account distributions
Schedule an account to pay a dollar amount or percentage into household cash, even in years when spending does not require a withdrawal.
3 min readChoose an inherited account’s withdrawal schedule
Model inherited IRA or Roth money with a deadline, annual distributions, or a life-expectancy schedule.
2 min readUse an HSA in the projection
Set coverage and employer contributions, then understand which modeled medical costs can support tax-free withdrawals.
2 min readSpending in retirement
Compare five ways to adjust spending as your portfolio changes.
5 guides
Guyton-Klinger spending guardrails
Adjust retirement spending when withdrawals become too large or too small relative to your portfolio, using upper and lower guardrails.
6 min readSpending a fixed share of the portfolio
Base each retirement year’s spending on a fixed percentage of the portfolio, so the budget moves with your account balances.
5 min readThe Bogleheads’ variable percentage withdrawal
Adjust retirement withdrawals using your portfolio balance and remaining planning horizon. The withdrawal percentage rises as the horizon shortens.
5 min readBob Clyatt’s 95% rule for retirement spending
Use a percentage of the portfolio for spending while limiting a reduction to 5% of the previous year’s portfolio-funded amount.
5 min readMichael Kitces’ spending ratchet
Increase retirement spending after sufficient inflation-adjusted portfolio growth. This rule gives raises without later cutting them back.
6 min readHomes & property
Plan purchases, sales, rental income, taxes, and the ongoing costs of ownership.
3 guides
Property upkeep and carrying costs
Account for maintenance, homeowners insurance, and association dues alongside your mortgage and property tax.
2 min readPlan a property purchase or sale
Connect purchase funding, mortgage payments, selling costs, and taxes to the years when a property is owned.
2 min readRead rental cash flow and taxable profit
See why rent collected, cash kept, and income reported for tax can be three different amounts.
2 min readSee the bigger picture
Follow your numbers through a year.
See how income, taxes, spending, and saving come together in your forecast.