Assumptions & Methodology

Tracks the Bloomberg US Aggregate Bond Index. Long-run historical average ~3.5%; recent 10-year average ~1.8% due to 2022 bond correction. RetireCiv uses the long-run figure for planning.

Treasury Reg. §1.401(a)(9)-9(c), T.D. 9930. RetireCiv enforces the RMD floor in drawdown: the retiree always withdraws at least the table amount once they reach the start age, even if it is not needed for expenses.

Only traditional TSP, traditional IRA, and 401(k) balances are counted; brokerage, cash and Other taxable accounts sit outside the RMD rules. Designated Roth accounts in employer plans carry no lifetime RMD (SECURE 2.0 §325, effective 2024), Roth IRAs never did. Your Roth share of the TSP comes from the Taxes and Deductions step; with that turned off the TSP is treated as fully traditional. A spouse’s TSP is also treated as fully traditional.

An RMD is a forced distribution, not forced spending. Whatever you do not need that year is returned to your portfolio as taxable savings, and it is not subject to RMDs again. It is not modeled as a separately allocated taxable account, so its yearly dividends and realized gains are not taxed as they accrue.

The survivor benefit is figured on your record: it is reduced when taken before their survivor full retirement age, and limited when you claimed early. It is not simply your own check.

Their own FERS annuity, Special Retirement Supplement, VA compensation and private pension are theirs, not survivor benefits, so your death does not stop them. Each counts only once it is being paid: their annuity from the date it begins and their supplement from then until 62. Their own Social Security enters the higher-of rule above only from their claiming age. PDF section 12 prints each one in payment at the death it models as its own row, and the Monte Carlo survivor phase pays each from the same age. Wages are handled differently. The Monte Carlo survivor phase keeps paying a working spouse’s wages until the age they stop work. PDF section 12 leaves those wages out, and says so when your spouse would still be working at the death it models.

If your spouse took a smaller annuity to provide a survivor benefit for you, that reduction ends at your death and their own annuity returns to its amount before the survivor reduction (any age reduction stays). Federal law ends it for each full month after the death (5 U.S.C. 8419(b)(1)(A)). PDF section 12 prints the full amount, and the Monte Carlo survivor phase applies the same rule in both directions: your own annuity returns to full if your spouse dies first and you had elected a survivor benefit for them.

VA disability compensation ends at the veteran’s death. Federal law pays the surviving spouse the amount you would have received for the month of your death (38 U.S.C. 5310(a)). Dependency and Indemnity Compensation is a separate VA benefit with its own eligibility, and we do not model it. The Monte Carlo survivor phase and PDF section 12 stop your VA compensation at your death.

Any mortgage or loan payment that ends before the modelled death comes out first, since your spouse would not be paying it. A loan with no payoff date entered ends when its balance, rate and payment would pay it off (a blank rate is read as 0%). Property tax and insurance stay. Credit card payments stay too. So does a loan whose payment does not cover its interest, or one with no balance entered, because neither has a payoff the calculator can work out. The Monte Carlo survivor phase drops the mortgage at the same payoff date.

Rental, business, investment and other income is assumed to keep paying your survivor, and PDF section 12 prints it as its own row. Part-time work stops at your death: we treat it as your own job, because the calculator does not ask whose job it is, so if your spouse is the one working, the survivor estimate is low. A pension you entered as other income stops at your death, as does the pension in your salary info, because the calculator does not ask whether it has a survivor provision. The Monte Carlo survivor phase and PDF section 12 apply the same rule.

A death while still working is a death in service. With at least 10 years of service, OPM pays the surviving spouse half of the annuity earned to the date of death, whatever survivor election was planned. The Monte Carlo simulation does not model this; it pays the survivor annuity the planned election would have provided.

Hours above the ceiling at the end of the leave year are forfeited (use or lose), so the payout projection caps the balance carried into each new leave year at your ceiling (5 U.S.C. §6304(a) for the 240-hour ceiling, §6304(b) for the 360-hour overseas ceiling, and §6304(f), which reads both limits as 90 days for SES, senior-level and scientific or professional positions).

Leave restored after an administrative error, an exigency of the public business, or sickness sits in a separate account outside the ceiling (§6304(d)). Enter it on the Leave step; it is paid in the lump sum.

Unused annual leave is paid as a lump sum at the pay you would have received had you stayed through the leave period (5 U.S.C. §5551); RetireCiv prices it at your projected separation-date salary.

Civilian FERS service only, rounded to the nearest whole year (5 U.S.C. §8421(b)(1); OPM RI 90-8). Bought-back military time and CSRS-component years count toward eligibility and the annuity, but are excluded from this fraction. RetireCiv subtracts them when you provide them in the wizard. RetireCiv uses your own Social Security estimate at 62 as an approximation; OPM computes its own full-career figure when you retire (CSRS/FERS Handbook ch. 51), so your actual supplement can differ.

5 U.S.C. §8421a(b)(4)(B)(ii). Special-provision retirees are not subject to the earnings test until they reach their Minimum Retirement Age; RetireCiv pays their SRS in full below MRA regardless of earnings. The exemption applies only when retiring under the special provisions themselves; a LEO who retires under VERA or DSR is subject to the test. RetireCiv models the SRS as a single first-year figure, so the MRA-to-62 portion is not separately earnings-tested.

The projection assumes your investments earn the same return every single year. Real markets do not. A plan that looks comfortable here can still fail in a bad decade, which is exactly what the Monte Carlo page is for: it runs thousands of varied market paths and reports how often your income covers your spending in every simulated year.

The "TSP at retirement" card grows your TSP at your fund allocation’s blended return, exactly as the dashboard and PDF do, so that figure matches them wherever you meet it. Everything else that compounds before retirement (spouse TSP, other investments except cash and savings accounts, which are held flat at balance plus contributions in every projection, the income chart’s accumulation) uses your saved annual return assumption from Settings. Lowering that assumption therefore moves the age at which the income you receive first falls short of the level you chose, often by years, while the balance card holds still; that is the two rates at work, not a bug. Because there is no volatility, each rate is applied without variation rather than as an average.

A separate control, because a portfolio you are drawing on is usually held more conservatively than one still growing. It starts at 4%, the Monte Carlo page’s default post-retirement average, rather than the higher rate assumed while you are working. Only the drawdown years change; your balance on the retirement date is unaffected.

Spending is the plan variable on the what-if page. You set it as the share of your current household salary (yours plus your spouse’s while it is still being paid) you expect to live on in retirement, which is how most retirement guidance is written; published ranges land between 55% and 80%. The slider opens at 80%, the top of the 55% to 80% band cited under the control, rather than at your entered-expense share, which understates a real retirement. Moving it is your decision. Your figure is in today’s dollars and is inflated to each future year. It drives how much comes out of your savings, when the income you receive first falls short of the level you chose, and what is left at the end.

When you have entered expenses, the chart draws a solid white line at that figure, inflated the same way. It does not move when you change the spending slider, though the spending-pattern control reshapes it, so it stays a fixed reference for how far a plan sits from your current life. Loan payments are excluded from it, because they end at their payoff dates. Your mortgage is handled the same way, in two parts: the principal and interest, including any extra principal you pay each month, are charged until the projected payoff date (which already assumes that extra) and stop there, and until then they are held flat rather than inflated, because a fixed-rate payment does not rise with prices. Property tax and insurance carry on and do inflate. With no expenses entered the line is not drawn at all rather than sitting at zero. The spending level you chose is not drawn as its own line, because in years the portfolio is being drawn on the stacked bars already add up to it (when guaranteed income runs above the chosen level, or once required minimum distributions begin, the bars show the larger amount actually received).

On the what-if page and in the Monte Carlo simulation alike, when the income you receive without drawing on the portfolio (your annuity, any SRS bridge, Social Security, VA compensation and pension; your spouse’s annuity, SRS bridge, Social Security, VA compensation, pension and wages; and other income) is larger than the spending level you chose, the difference is added to your savings and grows there for the rest of the projection. It is treated as taxable savings, so it is never subject to required minimum distributions later. This is why spending less leaves more behind even in years when you withdraw nothing at all. Only the money you could actually keep is saved: we first subtract an estimate of the federal income tax owed on that income. Without that step the balance would grow by dollars that belong to the IRS. The estimate assumes no state income tax, so it is deliberately on the low side.

The projection runs in future dollars, so the closing balance is stated in the money of the year it is reached, not in today’s money. Decades of inflation sit between the two: a figure at age 90 buys considerably less than the same number does now.

The projection withdraws what your plan actually needs: the gap between your spending and your guaranteed income, with the required minimum distribution as a floor. A withdrawal-rate setting would be a second, competing driver for the same number, so the what-if page does not have one. Your saved 4% assumption still drives the dashboard.

Because withdrawals are sized to cover the gap, total first-year income moves in step with whatever spending level you choose: raising the percentage raises the total, but only by drawing more from your own savings. Guaranteed income (FERS annuity, SRS, Social Security, VA compensation, and pensions) does not move with the slider, so it is the figure that tells you what the plan itself produces.

Every income figure on the what-if page is before tax. Your dashboard and the Monte Carlo page both offer an after-tax view when the Taxes and Deductions estimate is turned on. There is one exception, and it runs in your favor as a matter of accuracy: unspent income is taxed before it is added to your savings (see the row above). A balance is not a before-tax figure the way an income figure is, so growing it with untaxed money would simply overstate it.

The projection ends at the age you choose. The final year shown is the year you reach that age, counted as a full year of income and spending. A spouse who outlives you keeps the projection running on survivor income.

Balances and incomes reported by the simulation are in the dollars of the year they occur, not today’s money. A median ending balance decades out therefore looks larger than its purchasing power. The what-if projection states its own basis separately.

You set the average return on the Monte Carlo page: 7% by default. The spread is fixed at a 12% standard deviation, shown beside the slider: close to the spread of TSP L 2040 returns from 2006 to 2025 with today’s fund mix held fixed (tsp.gov). One return is drawn each month for the whole portfolio, at mean/12 and std/√12, so the yearly figures hold while each trial carries monthly sequence risk.

You set the average return on the Monte Carlo page: 4% by default. The spread is fixed at a 5% standard deviation: close to the spread of TSP L Income returns from 2006 to 2025 with today’s fund mix held fixed (tsp.gov). Same monthly draw.

Set on the Monte Carlo page; midpoint is the mean, half-width the standard deviation, so the default range runs at a 2.5% mean with a 1% standard deviation. Anchored on the SSA Trustees Report long-run CPI-W projection. Drawn per simulated year, clamped at ≥ −2% to prevent runaway deflation.

FERS COLAs are capped below CPI by the diet-COLA rule (5 U.S.C. §8462(b)); the age-62 start and its exceptions are §8462(c): if CPI ≥ 3% → CPI − 1%; 2%–3% → 2%; ≤ 2% → full CPI. The simulation applies your saved FERS COLA assumption as one flat rate every year (1.8% unless you change it in Settings), not the three bands against each year’s drawn inflation. Regular FERS receives no COLA until age 62; special-provision (LEO/FF/ATC) retirees begin COLA at retirement. (Disability retirees also start COLA at retirement under the statute, but the calculator does not model disability retirement.)

IRS Uniform Lifetime Table (Treasury Reg. §1.401(a)(9)-9(c)), applied to tax-deferred balances only. Drawdown withdraws at least the RMD amount from your start age onward, even if expenses would not require it; anything left unspent is returned to the portfolio as taxable savings.

5 U.S.C. §8421a. SRS reduced $1 per $2 of earned income above the annual SSA exempt amount. Retiring under the special provisions themselves exempts you until your Minimum Retirement Age; separating under VERA or DSR does not.

Your lifespan cap comes from your own slider; the two thumbs default to 80 and 90. Each simulated lifespan is drawn from your slider range itself: the mean is the midpoint and the standard deviation half the width (85 and 5 at the default 80 to 90), then capped at the top thumb unless the floor is higher: every run goes at least five years past your retirement age and at least a year past your current age, so a household already past the top of the range runs to that floor, never to a past age. With the survivor analysis on, the simulated horizon extends to the later of the two deaths so surviving-spouse years are still modeled.

A flat, easy-to-explain rate. Close to what Hurd and Rohwedder measured across every wealth quartile in the Health and Retirement Study, and the same simplification RightCapital ships in its own planning software.

Blanchett (2026), Equation 2. Tracks the median retiree, whose real spending keeps falling at older ages. The formula is slightly positive below age 63, so if you retire before then your spending rises a little first. It turns down around 63 and falls fastest in the 80s.

Blanchett (2026), Equation 1, unchanged from his 2014 paper. Tracks the average across all retirees. The formula is positive below age 65, so an early retiree spends more in real terms for the first several years (see Reading the patterns, below). After that it declines, and while it flattens in the late 80s, the upturn never restores your original standard of living: it only slows the decline.

Both formulas are second-order polynomials fitted to that range, and neither is valid outside it. We hold the rate flat below 60 and above 90. Extrapolating the smile to age 105 would produce a real spending increase of about 4.4% a year, which is the opposite of the finding it comes from.

A decline does not fall evenly on a budget. Following Blanchett’s own essential-versus-flexible split, we apply the pattern to 75% of your spending and hold the remaining 25% flat in real terms. Your mortgage principal and interest, including any extra principal you pay each month, are excluded entirely, on top of that: a fixed-rate payment does not shrink because you got older, and it stops at the payoff date that extra brings forward.

FEHB, FEDVIP, and Medicare premiums are handled separately in the optional taxes and deductions estimate: FEHB and FEDVIP grow at your healthcare inflation assumption, while Medicare Part B and IRMAA grow at the Social Security COLA. They are the one part of a retiree budget with strong evidence of real growth, so no spending pattern is ever applied to them.

The survivor spending level and the spending pattern are separate assumptions and they multiply. We apply the pattern first, then the survivor level. They do not double-count: the research only includes households whose marital status stayed the same across every survey, so a spouse dying is not part of the measured decline. It is a genuinely separate adjustment.

Your readiness score and replacement rate ignore whichever pattern you pick, the same way they always ignore taxes. A headline score should not improve because you chose a friendlier assumption.

Your FI number is 25 times your annual expenses, and those expenses include your debt payments, so paying off a loan lowers the number. Progress is your investment assets (home value excluded) divided by that number.