How much cash should I keep in my portfolio?

Keep an emergency fund of roughly three to six months of essential spending outside the portfolio first. Inside the portfolio, many long-term investors hold near zero while accumulating and build a one-to-three-year spending bridge approaching retirement. Backtest your own mix with a CASH holding to see the tradeoff in numbers.

The growth you give up by holding cash instead of higher-returning assets. If stocks earn 8% and cash 2%, every 10% of the portfolio in cash costs about 0.6% of return a year — which compounds into a large gap over decades.

Is holding cash to buy the dip a good strategy?

On average, no — markets rise more often than they fall, so cash waiting for a dip usually underperforms just being invested. A small cash buffer for rebalancing or peace of mind is reasonable; a large one as a timing strategy has historically cost more than it saved.

How Much Cash Should You Hold in a Portfolio?

6 min read · Updated 2026-07-18

Cash is the most comfortable asset you can own — it never crashes, never gaps down at the open, and it's there the day the car dies. It's also, over long stretches, one of the worst-performing things in a portfolio. Both facts are true at once, which is why “how much cash?” deserves a real answer instead of a vibe.

The useful move is to split the question in two: cash for your life, and cash inside your portfolio. They have different jobs, different right sizes, and only one of them should be judged against the market.

Backtest your cash allocation →

Cash for your life: the emergency fund comes first

Before any investing conversation, most people want a reserve that covers roughly three to six months of essential spending — more if your income is lumpy or your job is fragile. This money's job is availability, not return. It's what lets a job loss or a burst pipe stay an inconvenience instead of a forced sale of investments at the worst possible moment.

Judge the emergency fund by whether it lets you sleep and never touch the portfolio in a crisis. Don't judge it against the S&P 500 — that's not its job.

Cash inside the portfolio: the price is called drag

Once the emergency fund exists, every extra dollar of cash inside the portfolio is a choice with a price. Cash typically earns a bit above or below inflation; stocks and bonds are there because they're expected to earn more. The gap, compounded over decades, is “cash drag” — and it's bigger than most people guess.

The chart shows a hypothetical $100,000 invested for twenty years, with stocks assumed to earn 8% a year and cash 2% — deliberately round, illustrative numbers. The shape is what matters: drag is small at 5% cash and very real at 25%.

$100k after 20 years by cash allocation (illustrative: stocks 8%/yr, cash 2%/yr)

0% cash

$466k

5% cash

$441k

10% cash

$417k

25% cash

$352k

Stylized constant returns, annual rebalancing, no taxes. Backtest your own mix with a CASH holding to see the drag on real history.

When cash earns its keep

Drag isn't the whole story — cash buys things returns can't:

•Behavioral ballast — a cash cushion is often the difference between riding out a crash and selling into it. A drag you can live with beats a perfect allocation you abandon.
•A spending bridge in retirement — one to three years of withdrawals in cash means a bear market doesn't force selling stocks at the bottom (the classic sequence-risk defense).
•Known near-term bills — money needed within a couple of years (a house deposit, tuition) generally doesn't belong in stocks at all.
•Optionality — “dry powder” for rebalancing into a selloff. Honest caveat: on average, staying invested has beaten waiting for dips, so treat this as a bonus, not a strategy.

Put a number on it: test your cash level on real history

Rules of thumb only get you so far, because the right cash level depends on how the rest of your portfolio behaves. So test it: backtest your actual mix with 0%, 5%, 10%, and 20% held as cash — the backtester supports CASH as a holding — and compare growth, volatility, and maximum drawdown side by side. You'll see exactly how much calm each slice of cash bought, and what it cost.

Most investors land somewhere simple: a full emergency fund outside the portfolio, near-zero cash inside it while accumulating, and a deliberate cash bridge appearing in the years around retirement. Wherever you land, land there on purpose — with numbers you've seen, not a feeling.

Try it yourself

Backtest PortfolioAdd CASH as a holding and replay your exact mix through history.Open tool →Retirement Withdrawal LabSee how a cash bridge changes your plan's survival odds.Open tool →Stress Test / ScenariosCheck how much a cash cushion softens a 2008-style crash.Open tool →

FAQ

How much cash should I keep in my portfolio?: Keep an emergency fund of roughly three to six months of essential spending outside the portfolio first. Inside the portfolio, many long-term investors hold near zero while accumulating and build a one-to-three-year spending bridge approaching retirement. Backtest your own mix with a CASH holding to see the tradeoff in numbers.
What is cash drag?: The growth you give up by holding cash instead of higher-returning assets. If stocks earn 8% and cash 2%, every 10% of the portfolio in cash costs about 0.6% of return a year — which compounds into a large gap over decades.
Is holding cash to buy the dip a good strategy?: On average, no — markets rise more often than they fall, so cash waiting for a dip usually underperforms just being invested. A small cash buffer for rebalancing or peace of mind is reasonable; a large one as a timing strategy has historically cost more than it saved.

Key terms in this guide

Plain-English definitions in the Learning Hub.

Maximum drawdown →Volatility (annualized standard deviation) →Sequence-of-returns risk →CAGR (Compound Annual Growth Rate) →

Stop guessing — run the numbers on your own portfolio, free.