Coast FIRE Number at 31

Retiring at 65 with a 7% return, 3% inflation and a 4% withdrawal rate, in today's dollars.

How fast you get there from $70,000

Starting at 31 with $70,000 invested and planning to spend $60,000 a year, here's when you'd cross the line at different monthly contributions.

At 31, a lot of people are trying to buy a first home and keep their retirement savings going at the same time, often within a year or two of getting married. Something usually gives. If it’s your 401(k), the pause costs more than its length, and it’s worth knowing the price before you agree to it.

Why does a two-year pause cost more than two years?

Your Coast FIRE number isn’t fixed. It’s the amount that would grow to your full retirement target by 65 with no more help from you, and every year you get closer to 65 there’s one less year of growth to do that work. So the target rises every year, by roughly the real return, and it does so in the years you skip as well.

During a pause, your balance still grows with the market. It just stops getting new money, and the gap between where you are and where you need to be widens every month. When contributions restart, the first stretch of them goes to closing that gap before they start moving you forward again. That’s why two years off can mean three or four years later at the other end.

Losing the employer match makes it worse. If you stop contributing, most plans stop matching, and that’s money you can’t make up later at any contribution rate.

Sofia and Paolo at 31

Sofia and Paolo are both 31 and got married last year. Between them they have $110,000 invested, and they put $3,000 a month into their two 401(k)s: $2,200 of their own money plus $800 in employer matches. They’d like $60,000 for a down payment in about two years, and they expect to spend $75,000 a year once they retire. Their Coast FIRE number is $513,356, and they have 21% of it.

The full pause moves them from 45 to 49. To get back to 45 after a two-year break, they’d have to contribute about $3,650 a month from 33 onward instead of $3,000, every month, for as long as it takes. That’s the real bill for the pause, and it arrives in their mid-30s, when a new mortgage and possibly kids are competing for the same money.

The middle row is the one I’d pick. Keeping just enough going to collect both matches frees up $1,400 a month of their own money for the down payment, and it keeps them well ahead of the full pause. If that means waiting a few extra months to buy, I think that’s a good trade.

Where else can the down payment come from?

A Roth IRA is more flexible than people think. Withdrawals are treated as coming from your regular contributions first, and those come out without income tax (IRS Publication 590-B). Earnings are different. Up to $10,000 of IRA money used for a first home escapes the 10% additional tax, but it’s a lifetime limit, and Roth earnings come out fully tax-free only once five tax years have passed since your first Roth IRA contribution. For this rule, a first-time buyer is anyone who hasn’t owned a main home in the past two years, and a spouse has to meet that test too.

A 401(k) loan is the other common route, if your plan allows loans. You can generally borrow up to half your vested balance, capped at $50,000, and a loan used to buy your main home can be repaid over more than the usual five years (IRS plan loan rules). I’m wary of it at this age. If you leave the job with a balance outstanding, the plan can offset the loan against your account, and unless you roll over that amount by your tax filing deadline, including extensions, it’s taxed as a distribution. At 31, a job change in the next five years is likely.

What marriage changes in the math

Your number is now a household number. Plan around what the two of you will spend together, which is usually well under double what either of you would spend alone, and set it against all your accounts combined. If your ages or balances are far apart, the couples calculator takes both of you separately.

Compare your two matches as well. If one plan matches 6% and the other matches 3%, the first dollars of household savings should go to the more generous one. Once both are maxed, a paid-off house by 65 is worth considering because it lowers your retirement spending, and paying the mortgage early versus investing walks through when that makes sense.

Other ages: 25, 28, 30, 32, 35, 40, 45, 50, 55. Or see every age on one table.