Your expected retirement year is literally the product's name. A TDF (Target Date Fund) calls the four-digit number in its name the vintage, and that number marks the target retirement point. The fund automatically shifts the mix of stocks and bonds toward that date. But what actually parts your outcome comes down to three things: which vintage you pick, how fast the fund cuts risk assets (the glide path), and the combined total expense ratio charged every year. Pick by the name alone and your 20-year balance can differ by millions of won.
Vintage is usually set by adding your expected retirement age to your birth year. As KB explains, someone born in 1990 assuming retirement at 60 lands on 2050, so they pick TDF2050. That is where the birth-year-plus-60 rule of thumb comes from.
You don't have to match your exact retirement year
TDFs are issued only in five-year steps (2030, 2035, 2040, 2045, 2050). So if you expect to retire in 2038, no exact product exists. You take the nearest 2040, but you can shift the target earlier to 2035 for a steadier ride, or later to 2045 to run a bit more aggressively. A lower vintage (closer retirement) carries more bonds and moves less; a higher vintage carries more stocks and swings more.
In other words, vintage is less about your age than about the volatility you can stomach. If retirement is more than 20 years away, there is little reason to lower a vintage and cap your upside; if it is right around the corner, a high vintage's stock weight becomes a burden.
Glide path: the speed of cutting risk differs by product
Even within 2050, each asset manager lowers stock weight along a different route. That route is the glide path. Early on, with 30 years to retirement, risk assets may sit near 80%; as the date nears, they step down below 40% around retirement. The key question is where the descent stops. A "To" approach ends the descent at retirement; a "Through" approach keeps lowering stock weight past retirement. As Fastcampus notes, a TDF follows its preset path regardless of market conditions, so it will not change the mix even when bonds fall sharply. This static nature is both its strength and its limit.
A TDF boils down to two levers—when you retire (vintage) and how fast it cuts risk (glide path). Reading only the number in the name means you've chosen just half of it.
0.4% vs 1.5% total fees: how far apart after 20 years?
The third lever is cost. Because a TDF is a fund-of-funds, the headline fee isn't enough—you need the combined total expense ratio. Per KB, domestic TDF fees run around 0.40% a year in DC accounts and roughly 0.21–0.45% in personal IRPs, but funds-of-funds that subcontract to overseas managers can reach about 1.5% on a combined basis, as Fastcampus describes. To see how that compounds, I ran the numbers on 10 million won at an assumed 5% gross annual return over 20 years.
| Total expense ratio | Net return (5% − fee) | Balance after 20 yrs | Gain over principal |
|---|---|---|---|
| 0.40% | 4.60% | approx. 24.58M won | +14.58M won |
| 1.00% | 4.00% | approx. 21.91M won | +11.91M won |
| 1.50% | 3.50% | approx. 19.90M won | +9.90M won |
The gap between 0.40% and 1.50% is about 4.68 million won after 20 years—nearly half the principal, decided purely by the annual fee difference. Since the gross return is held equal, between two similar funds the cheaper one is that much ahead. If you hold it inside a pension account, apply the same yardstick you'd use for weighing a pension-savings ETF's total fees.
Active vs. passive: what differs
As Toss Bank explains, the same vintage can be run in different styles. An active fund responds more to market shifts but charges more and swings more. A passive fund tracks fixed indices with lower fees and more predictable results. Neither is flatly better; it is a trade-off between the volatility you'll accept and the fees you'll bear. Even funds that look the same on risk rating differ in actual composition, so always check the prospectus's risk grade and asset mix.
What to watch before choosing
- Vintage: set it by birth year plus retirement age, then nudge one step up or down for the volatility you can handle
- Glide path: compare current stock weight and the To/Through style across same-vintage funds
- Total fees: compare the combined ratio, not the headline fee—when performance is similar, fees decide
- Account fit: to gauge the effect inside tax-advantaged accounts, pair this with the pension-account tax-deduction math
- Static by design: assume it won't rebalance even in a market shock
