How much do I need to retire? The 25x rule, explained

"How much do I need to retire?" feels like it should require a spreadsheet, an advisor and a crystal ball. In reality, a back-of-the-envelope answer takes about ten seconds once you know one number: how much you expect to spend each year. Everything else — the famous 4% rule, the 25x multiplier, your "retirement number" — is built on that single figure.

The 25x rule in one line

The quickest estimate in personal finance is this:

Annual spending × 25 = the nest egg you need

If you expect to spend $50,000 a year in retirement, you aim for roughly $1.25 million. Spend $40,000 and the target falls to $1 million; spend $80,000 and it climbs to $2 million. The math is deliberately blunt, but it gives you a real, defensible goal to plan toward — and it scales perfectly with your own lifestyle rather than someone else's.

Where 25x comes from: the 4% rule

The 25x rule is just the 4% rule wearing a different hat. The 4% safe-withdrawal rule says that in your first year of retirement you can withdraw about 4% of your portfolio, then increase that dollar amount with inflation each year, and have a strong chance of your money lasting roughly 30 years.

Flip 4% upside down and you get 25:

1 ÷ 0.04 = 25

So "withdraw 4% a year" and "save 25 times your annual spending" are the same statement said two ways. The figure traces back to the 1990s "Trinity Study" and William Bengen's research, which tested historical US stock-and-bond portfolios across every 30-year window they could find. A 4% starting rate survived almost all of them.

It is a planning anchor, not a promise. Long retirements, stubbornly low bond yields, and a bad run of returns in your first few years can all strain it, which is why many cautious planners now use 3.5% (about 28.5x spending) instead. Use 4% to get your ballpark, then tighten it if you want more margin.

Step one: estimate your retirement spending

The whole calculation hinges on your spending number, so it is worth getting honest about it. The cleanest method is to start from what you spend now and adjust:

• Subtract costs that usually disappear — commuting, work clothes, the retirement-savings contributions you no longer make, and a mortgage if it is paid off by then.
• Add costs that often rise — healthcare and insurance, travel, hobbies, and helping family.

Many households land around 70–85% of their pre-retirement spending, but that is a sanity check, not a substitute for building your own budget. A person who retires with a paid-off house and Medicare looks very different from one still renting in a high-cost city. Run your real numbers.

Spending vs nest egg: the table

Because the rule is pure multiplication, you can read your target straight off a table. The middle column uses the classic 4% rule (25x); the right column shows the more conservative 3.5% rule (about 28.5x) for comparison.

Annual spending in retirement	Nest egg at 4% (25x)	Nest egg at 3.5% (≈28.5x)
$30,000	$750,000	$857,000
$40,000	$1,000,000	$1,143,000
$50,000	$1,250,000	$1,429,000
$60,000	$1,500,000	$1,714,000
$80,000	$2,000,000	$2,286,000
$100,000	$2,500,000	$2,857,000

Illustrative figures using the 25x (4%) and ≈28.5x (3.5%) rules of thumb. They ignore taxes, Social Security and any pension — all of which change your real target. Always model your own situation.

Social Security shrinks the number — a lot

Here is the part the basic 25x rule leaves out, and it is the best news in this article: you do not have to fund all of your spending from savings. Social Security, a pension, an annuity or rental income can each cover a slice, and you only need to save enough to fill the gap.

The math is simple — subtract guaranteed income from your spending before you multiply:

(Annual spending − guaranteed income) × 25 = savings you actually need

Worked example

Say you plan to spend $50,000 a year. The naive 25x target is $1.25 million. Now suppose Social Security will pay you $24,000 a year (a realistic figure for a middle earner claiming at full retirement age — the 2024 average benefit ran around $1,900 a month):

Step	Amount
Planned annual spending	$50,000
Less: Social Security income	−$24,000
Gap to fund from savings	$26,000
Nest egg needed (gap × 25)	$650,000

Illustrative only. Your benefit depends on your earnings history and claiming age; check your personalized estimate at ssa.gov. Taxes on withdrawals and benefits are not modeled here.

Social Security cut the savings target almost in half — from $1.25 million to $650,000. That is why "how much do I need to retire?" has no universal answer: it bends entirely around how much guaranteed income you will have. Always estimate your benefit before you panic about the headline number.

Three things that move the target

1. Inflation

The 4% rule already bakes in inflation — that is the point of raising your withdrawal each year to keep pace with prices. But it means your nest egg has to keep growing, which is why retirement portfolios still hold a meaningful chunk of stocks rather than sitting entirely in cash. Plan in today's dollars and let the inflation adjustment do its work; a calculator that quietly assumes you'll never get a raise will scare you for no reason.

2. Healthcare costs

Healthcare is the line item most likely to blow up an otherwise tidy budget, especially before Medicare kicks in at 65. Premiums, out-of-pocket costs and long-term care can add tens of thousands a year for a couple. If you plan to retire early, build a generous healthcare line into your spending estimate before you multiply by 25 — it is far cheaper to over-budget on paper than to discover the shortfall at 62.

3. Sequence-of-returns risk

This is the quiet danger behind the 4% rule. A market crash in your first few years of retirement hurts far more than the same crash twenty years in, because you are selling assets to live on while they are down — locking in losses you never recover. Two retirees with identical average returns can end up in very different places purely based on the order those returns arrive. The usual defenses: keep a cash or bond buffer of one to three years of spending, stay flexible enough to trim withdrawals in a bad year, and avoid retiring with 100% of your money in stocks.

Putting it together

A workable answer to "how much do I need to retire?" takes four steps: estimate your annual spending, subtract any guaranteed income, multiply the gap by 25 (or 28.5 if you want more cushion), and then sanity-check it against inflation, healthcare and the order of your early returns. The first three steps give you a number in minutes. The fourth is what turns a number into a plan.

If you are still in the accumulation phase, the more useful question is often "am I saving enough per year to get there?" Our retirement and 401(k) calculator projects how your contributions grow over time, and the guide on how much you should have in your 401(k) by age gives you benchmarks to check yourself against along the way.

Frequently asked questions