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Asset allocation by age: A practical glide path

A practical stock/bond glide path, decade by decade. Plus the three-fund portfolio that makes this trivial to actually execute.

Jahanzeb Nawaz — Founder, FinBrief

Written by

Jahanzeb Nawaz

Founder, FinBrief

Reviewed by the FinBrief Editorial Team

Updated · 11 min read

Asset allocation — your stock/bond split — drives the vast majority of your portfolio's risk and return. It matters more than picking the "right" funds. More than market timing. More than tax-loss harvesting. Get this one decision roughly right, then automate everything around it.


The baseline glide path

We use 120-minus-age in stocks as the baseline — more aggressive than the older 100-minus-age rule, because retirements now last 30+ years and bond yields have been lower than historical averages for the past two decades.

AgeStocksBondsNotes
20s90–100%0–10%Maximum equity. 40-year time horizon.
30s85–90%10–15%Still very aggressive. Start adding bonds at age 35.
40s75–80%20–25%Peak earning years. Begin meaningful diversification.
50s65–70%30–35%Critical decade — sequence-of-returns risk starts mattering.
60s (pre-retirement)55–60%40–45%Build a 2–3 year cash/bond bucket for early retirement.
65 (retirement)50–55%45–50%Glide-path low point; still need 50%+ stocks for 30-year horizon.
70s+40–50%50–60%Mostly stable; tilt slightly more conservative if portfolio is large.

Why we don't use 100-minus-age anymore

The classic "100 minus age in stocks" rule was articulated when:

  • Average US life expectancy at 65 was ~14 more years (now ~20).
  • Bond yields averaged 5–7% (today's nominal Treasury yields are ~4%, real yields under 2%).
  • Retirements often meant a pension + Social Security + modest savings, not portfolio-funded withdrawals.

All three have flipped. Modern retirees need their portfolio to last longer, with bonds generating less, and few have pensions. The math just doesn't support 60% bonds at 65 anymore.


The three-fund portfolio

The simplest implementation that delivers on this glide path is the three-fund portfolio: total US stocks + total international stocks + total US bonds.

Example: age 35, target 85/15.

  • 60% US total stock market (VTI / FZROX / VTSAX)
  • 25% international total stock (VXUS / FZILX / VTIAX)
  • 15% US total bond (BND / FXNAX / VBTLX)

Example: age 55, target 70/30.

  • 50% US total stock market
  • 20% international total stock
  • 30% US total bond

That's it. Three funds, rebalanced annually, with new contributions directed to the underweight bucket. Decades of research show that adding fund #4, #5, or #6 rarely improves risk-adjusted return enough to justify the complexity.


How risk tolerance shifts the dial

The glide path above is a baseline. Adjust ±10 percentage points in stocks based on your honest answer to: "If my portfolio dropped 35% in 12 months, what would I do?"

  • "Keep buying more." Add 10 points to your equity %.
  • "Stay the course, don't change anything." Use the baseline.
  • "I'd panic-sell." Subtract 10 points. Going more conservative protects against the worst behavioral mistake — selling at the bottom.

The right allocation isn't the most mathematically optimal one. It's the one you'll actually hold through a bear market without panic-selling.


Sequence-of-returns risk — why your 50s and 60s matter most

The order of returns matters far more in your withdrawal years than in your accumulation years. Two retirees with the same average 30-year return can have wildly different outcomes if one experienced bad returns early in retirement and the other experienced them late.

A 2000-retiree who held 80% stocks took a 50%+ portfolio drawdown in 2000–2002, started withdrawing 4%/year anyway, and many ran out of money by 2020. A 1990-retiree with the same allocation rode strong returns up front and ended 30 years with more money than they started with.

Mitigation: in the 5 years before and after retirement, your bond allocation matters most. A 30–40% bond cushion lets you draw from bonds during equity bear markets while stocks recover. That's why the glide path bottoms at 50/50, not 80/20.


The bucket strategy (retirement)

Some retirees implement asset allocation as three "buckets" rather than percentages:

  • Bucket 1: Cash + short-term. 1–2 years of expenses in HYSA, money market, or short-term bonds. Drawn down for monthly living expenses.
  • Bucket 2: Bonds + intermediate. 5–7 years of expenses in total bond market funds. Refills bucket 1 every 1–2 years.
  • Bucket 3: Stocks. Everything else, fully invested in equities. Refills bucket 2 every 3–5 years (or when stocks are up).

Functionally identical to a percentage-based allocation, but psychologically easier in bear markets — you're not "selling stocks at a loss," you're using your "cash bucket" that was always meant for this.


Rebalancing — when and how

  1. Calendar rebalance once per year. Pick a date (birthday, year-end), check actual vs. target, sell overweights, buy underweights.
  2. Threshold rebalance. Rebalance whenever any asset class drifts more than 5 percentage points from target. (80/20 portfolio → rebalance when stocks hit 85% or 75%.)
  3. Cash-flow rebalance. Direct new contributions to the underweight bucket. This handles most rebalancing without ever selling.

Where to rebalance

Always rebalance in tax-advantaged accounts first (401(k), IRA, Roth IRA, HSA) — they're tax-free trades. Avoid rebalancing in a taxable brokerage account unless you're tax-loss harvesting; selling appreciated positions in taxable triggers capital gains.


Robo-advisors as a one-decision solution

If you don't want to manage allocation yourself, a robo-advisor will set the allocation from a questionnaire and rebalance automatically:

Try Betterment → Wealthfront

Or if you'd rather hold the underlying index funds yourself (lower fees, more flexibility), open at one of the major brokerages and use a target-date fund or three-fund portfolio:

Open a Fidelity account → Vanguard Schwab


What about gold, crypto, alternatives?

Most diversified investors don't need any alternatives. If you want exposure for psychological diversification:

  • Gold: 0–5% of portfolio. Inflation hedge, but long-term real returns are near zero.
  • Bitcoin: 0–3% of portfolio if you can stomach extreme volatility. Treat as a speculative asset, not a core holding.
  • REITs: Already in total stock market index funds via real-estate stocks. A dedicated REIT allocation is optional, not required.

None of these change the core glide path. They're rounding errors on top.


The bottom line

  • 20s/30s: 85–100% stocks. Maximum equity exposure during the longest compounding window.
  • 40s: 75–80% stocks. Begin meaningful bond diversification.
  • 50s: 65–70% stocks. Build the bond cushion that protects against sequence-of-returns risk at retirement.
  • 60s/70s: 50–60% stocks. Lower glide-path floor, but never go full conservative — your portfolio still needs to last 30 years.

Use a three-fund portfolio (US stocks / international stocks / US bonds) or a single target-date fund. Rebalance once per year. Direct new contributions to the underweight bucket. Don't panic in bear markets.

Related reading

Frequently asked questions

What's the 100-minus-age rule?
An old heuristic: subtract your age from 100 and that's your stock %. At 30, hold 70% stocks. At 60, hold 40%. Most modern advisors use 110 or 120 minus age instead, since retirements now last 30+ years and bonds yield less than they did historically. We use 120-minus-age as the baseline in this article.
Why have stocks at all if I'm close to retirement?
Because retirement isn't a single moment — it's 25–35 years of withdrawals. A 65-year-old retiree needs portfolio growth to outlast inflation through their late 80s/90s. The classic mistake is going 'all bonds' at retirement and watching purchasing power erode for three decades.
What counts as 'bonds' in this context?
Investment-grade fixed income — typically a total bond market index fund (BND, FXNAX, AGG) holding US Treasuries and investment-grade corporates. Stable-value funds, money-market funds, and short-term CDs also count as the 'safe' side of the portfolio in retirement.
Should I add international stocks?
Yes — most advisors recommend 20–40% of the equity sleeve in international stocks (VXUS, IXUS, VTIAX). For simplicity, you can also use a total world stock fund (VT) which is automatically ~60/40 US/international. Don't overthink the international % — anything between 20% and 50% of equities is reasonable.
What about target-date funds?
Target-date funds (Vanguard Target Retirement, Fidelity Freedom Index, Schwab Target) execute this glide path automatically. They adjust the stock/bond mix yearly based on the target retirement year. If you don't want to manage allocation yourself, a single target-date fund is the cleanest one-decision solution.
How often should I rebalance?
Once per year, or whenever any major asset class drifts more than 5 percentage points from target. Many investors rebalance automatically with new contributions (buy the underweight asset class). Tax-advantaged accounts are the cheapest place to rebalance since there's no capital gains tax on the sale.