Projection
?
How this model works
Timeline & currency. Monthly simulation from today until the youngest person reaches 115. All figures are in today's pounds (real terms) — drawdown, contributions and income stay constant by default because real purchasing power is what matters.
Pots grow monthly at (nominal return − fees), deflated by inflation to give a real-terms rate. Contributions stop at each person's Retirement age. Each pot has an access-from age; before it, the pot still grows but can't fund drawdown.
Income streams (state pension, DB pension, etc.) pay into a notional cash balance from their start age. Inflation-linked streams stay flat in today's money; non-linked ones erode. Cash balances don't earn interest.
Drawdown is household-wide. Each retired person contributes a monthly spending target based on their strategy (fixed £, % of pot at retirement, or % of current pot). In the % modes, active income streams are added on top. The household then draws the total, first from income-stream balances, then proportionally from each owner's accessible pots.
Lump sums (inheritance, house sale) land at the chosen age and are deposited proportionally across the owner's pots by balance.
Tax (UK 2024/25, per person per year). Withdrawals from Pension pots are 25% tax-free / 75% taxable; ISA, GIA and Cash withdrawals are tax-free here (GIA/Cash growth tax is assumed absorbed in the return). Taxable income streams (state pension, DB pension) count at receipt. UK bands applied individually: Personal Allowance £12,570, basic 20%, higher 40%, additional 45%. Income chart shows net after tax; the stat shows median lifetime tax.
Monte Carlo. Returns vary year-to-year around your pot assumptions. Normal mode draws each year independently with the set σ. Historical mode samples 5-year blocks from S&P 500 annual total returns (1928–2024) so crisis clustering survives resampling. Bands on each chart show p10/25/50/75/90 across trials.
Mortality. "Chance you outlive your pot" uses ONS UK Life Tables 2020–22 (unisex average) — per-year exhaustion probability weighted by the joint survival curve of the household.
Not modelled: PA taper above £100k, Scottish rates, CGT on GIA growth, dividend/savings allowances, lump-sum timing, MPAA, IHT, annuity purchase, long-term care costs, asset-allocation glide paths.
Timeline & currency. Monthly simulation from today until the youngest person reaches 115. All figures are in today's pounds (real terms) — drawdown, contributions and income stay constant by default because real purchasing power is what matters.
Pots grow monthly at (nominal return − fees), deflated by inflation to give a real-terms rate. Contributions stop at each person's Retirement age. Each pot has an access-from age; before it, the pot still grows but can't fund drawdown.
Income streams (state pension, DB pension, etc.) pay into a notional cash balance from their start age. Inflation-linked streams stay flat in today's money; non-linked ones erode. Cash balances don't earn interest.
Drawdown is household-wide. Each retired person contributes a monthly spending target based on their strategy (fixed £, % of pot at retirement, or % of current pot). In the % modes, active income streams are added on top. The household then draws the total, first from income-stream balances, then proportionally from each owner's accessible pots.
Lump sums (inheritance, house sale) land at the chosen age and are deposited proportionally across the owner's pots by balance.
Tax (UK 2024/25, per person per year). Withdrawals from Pension pots are 25% tax-free / 75% taxable; ISA, GIA and Cash withdrawals are tax-free here (GIA/Cash growth tax is assumed absorbed in the return). Taxable income streams (state pension, DB pension) count at receipt. UK bands applied individually: Personal Allowance £12,570, basic 20%, higher 40%, additional 45%. Income chart shows net after tax; the stat shows median lifetime tax.
Monte Carlo. Returns vary year-to-year around your pot assumptions. Normal mode draws each year independently with the set σ. Historical mode samples 5-year blocks from S&P 500 annual total returns (1928–2024) so crisis clustering survives resampling. Bands on each chart show p10/25/50/75/90 across trials.
Mortality. "Chance you outlive your pot" uses ONS UK Life Tables 2020–22 (unisex average) — per-year exhaustion probability weighted by the joint survival curve of the household.
Not modelled: PA taper above £100k, Scottish rates, CGT on GIA growth, dividend/savings allowances, lump-sum timing, MPAA, IHT, annuity purchase, long-term care costs, asset-allocation glide paths.
Monte Carlo uncertainty around your expected returns
Running simulation…
Median pot at retirement
—
Total contributed
—
Median lifetime tax
?
Total UK income tax paid across retirement, at the MC
median outcome. Applies 2024/25 bands per person:
Personal Allowance £12,570, basic 20% to £50,270,
higher 40% to £125,140, additional 45%. Pension
withdrawals treated as 25% tax-free + 75% taxable. ISA,
GIA and Cash withdrawals are tax-free at the point of
withdrawal (GIA/Cash growth tax is assumed absorbed in
the expected return).
—
Pot lasts (deterministic)
—
Annual household income, by age
Chance the combined pot is exhausted, by age
Chance you outlive your pot
?
Probability the combined pot runs out while you (or your
partner) is still alive. Per-year exhaustion probability is
weighted by the joint survival curve from ONS UK National
Life Tables 2020–22 (unisex). For couples, "alive" means at
least one of you.
Rough guide (typical advisor targets):
0–5% very safe (4% rule territory)
5–10% comfortable
10–20% moderate — consider trimming
20–40% noticeable risk
40%+ plan likely needs reworking
Levers to lower it: smaller drawdown, later Retirement age, lower fees, larger pot, more diversification.
Rough guide (typical advisor targets):
0–5% very safe (4% rule territory)
5–10% comfortable
10–20% moderate — consider trimming
20–40% noticeable risk
40%+ plan likely needs reworking
Levers to lower it: smaller drawdown, later Retirement age, lower fees, larger pot, more diversification.
—
—
—