Short vs Intermediate vs Long-Term
Short vs Intermediate vs Long-Term
Bond portfolios benefit from diversifying across maturity buckets. Short-term bonds dampen volatility; intermediate bonds balance yield and stability; long-term bonds amplify interest rate exposure and potential capital gains.
Key takeaways
- Duration (years of interest rate sensitivity) increases with bond maturity. Short-term bonds have 1-3 years of duration; intermediate 3-7 years; long-term 7+ years.
- A 1% rise in rates causes roughly a 1% loss for each year of duration. A 10-year-duration bond falls 10% when rates rise 1%.
- Short-term bonds offer stability and higher yields when the yield curve is steep (short rates lower than long rates); intermediate bonds offer balance; long-term bonds offer upside if rates fall.
- Strategic allocation across duration tiers depends on interest rate expectations and time horizon. Retirees typically hold more short/intermediate; young investors can tolerate more long-term.
- Laddering (holding bonds across all maturities) avoids the need to forecast rates and ensures predictable cash flows.
Duration: the measure of interest rate risk
Duration is the primary measure of a bond's sensitivity to interest rate changes. A bond with 5 years of duration loses approximately 5% in price if interest rates rise 1%. Conversely, it gains 5% if rates fall 1%.
Duration increases with maturity (longer bonds have longer duration) and decreases with coupon (higher coupon bonds have lower duration because the cash flows come sooner, reducing the weighted average time until maturity). A 30-year bond with a 0.5% coupon has higher duration (perhaps 20 years) than a 30-year bond with a 4% coupon (perhaps 12 years).
As of early 2025, typical durations are:
- Money market funds: 0.01 years (essentially no interest rate sensitivity)
- Short-term bond funds (1-3 year Treasury): 1-2 years of duration
- Intermediate bond funds (3-10 year Treasury): 4-6 years of duration
- Long-term bond funds (20+ year Treasury): 12-17 years of duration
- Aggregate bond fund: 5-6 years of duration (weighted blend of all maturities)
Short-term bonds: 1-3 year duration
Short-term bond funds (such as short-term Treasury or corporate funds) hold bonds maturing in 1-3 years. Duration is 1-2 years, meaning a 1% rate rise causes roughly a 1-2% loss. The flip side: a 1% rate fall causes a 1-2% gain.
These bonds are rarely attractive on a yield basis. As of early 2025, 2-year Treasuries yield about 3.8%, while 10-year Treasuries yield 4.1%. The yield pickup for holding 8 more years of duration is only 0.3%. Why would an investor accept 8 more years of interest rate risk for 0.3% more yield?
Short-term bonds are useful in specific scenarios:
- A retiree within 3 years of needing the principal. Buying 1-3 year bonds ensures predictable principal return and allows reinvestment at future rates.
- An investor with excess cash earning money market rates (0.5% or less) might buy short-term bonds yielding 3.5-4.0% to capture higher income with minimal rate risk.
- An investor expecting rates to rise significantly. If you expect the 10-year to yield 5% (up from current 4.1%), waiting in short-term bonds avoids locking in low long-term rates.
Intermediate bonds: 3-7 year duration
Intermediate bond funds (such as VGIT or AGG/BND) hold bonds in the 3-10 year maturity range. Duration is typically 4-6 years, a middle ground between short and long.
As of early 2025, intermediate bonds yield about 4.0-4.2%, slightly above short-term bonds but well below long-term bonds (which yield 4.3-4.5%). The Goldilocks yield—not the highest, but with much less duration risk than long bonds.
Intermediate bonds are suitable for:
- A balanced investor without strong interest rate convictions. The 4-6 year duration captures meaningful yield without excessive volatility.
- A retiree or near-retiree (5-15 years from full retirement). Intermediate bonds mature gradually over the near-term years and provide income when needed.
- An investor accumulating capital over several years. Intermediate bond ladders (buying a variety of intermediate maturities) provide predictable returns and reduce timing risk.
The aggregate bond fund (BND, AGG) is approximately 50% intermediate bonds, making intermediate exposure the core default.
Long-term bonds: 7+ year duration
Long-term bond funds (such as TLT or GOVT) hold bonds maturing in 20+ years. Duration is typically 12-17 years, meaning a 1% rate rise causes 12-17% losses. Conversely, a 1% rate fall creates 12-17% gains.
Long-term bonds are useful for investors who:
- Expect interest rates to fall. If rates decline from 4% to 3%, a 15-year-duration bond gains 15%, a spectacular return. Conversely, if rates rise, losses are severe.
- Have 20+ year time horizons and don't need the principal for decades. The extraordinary duration volatility is irrelevant if you're not selling.
- Want to hedge inflation-related risks. Long bonds sometimes perform well during reflation (inflation rises but more slowly than expected, causing rates to fall).
The risk of long-term bonds is severe in rising-rate environments. During 2022, the 10-year Treasury yield rose from 1.5% to 4.2%, a massive move. Long-term bonds (especially TLT, which holds 20+ year bonds) fell 20-30%. Investors who bought long bonds in early 2022 expecting rates to stabilize instead experienced losses.
By contrast, short-term bonds (like VGIT) fell only 3-5% in 2022, offering much more stability.
The yield curve and steepness
The shape of the yield curve (the plot of yields across maturities) matters. When short rates are much lower than long rates (a steep curve), owning intermediate or long bonds captures extra yield for accepting extra duration. When short rates are similar to long rates (a flat or inverted curve), there's little compensation for duration.
As of early 2025, the yield curve is near-flat: 2-year yields are 3.8%, 10-year yields are 4.1%, and 30-year yields are 4.4%. The curve has flattened over 2022-2024 as short rates (controlled by the Federal Reserve) remained elevated while long rates fell. This flat curve offers little incentive to own long bonds—the extra 0.6% yield for 20 more years of duration is meager.
In a steep curve environment (say, 2-year at 1.5%, 10-year at 4.0%), the 2.5% yield pickup would be more attractive, encouraging investors to extend duration.
Sophisticated investors use the yield curve to inform allocation. In a steep curve, extend duration (favor intermediate and long bonds). In a flat curve, shorten duration (favor short and intermediate bonds).
Laddering: a duration strategy
Many investors construct bond ladders to avoid interest rate forecasting altogether. A ladder holds bonds across all maturities (short, intermediate, long) in equal dollar amounts. As each bond matures, the proceeds are reinvested at the new (long) end of the ladder.
Example: A $100,000 bond ladder:
- $10,000 in 1-year bonds
- $10,000 in 2-year bonds
- $10,000 in 3-year bonds
- ... (continuing through 10-year bonds)
- $10,000 in 10-year bonds
Total: 10 rungs, $10,000 each, ladder duration approximately 5.5 years.
When the 1-year bond matures, the $10,000 is reinvested in a new 10-year bond. The ladder "rolls over," automatically capturing new rates without market timing. If rates rise, new 10-year bonds yield more, a benefit. If rates fall, you lock in low yields, a cost. Across many ladders, the timing effect averages out.
Laddering is useful for:
- Retirees who need predictable cash flows. Each rung matures every year, generating income.
- Conservative investors who don't want to forecast rates. The ladder captures whatever rates prevail without requiring foresight.
- Investors willing to assemble the ladder manually (buying individual bonds from a broker). Ladders work best with Treasuries (low trading costs) rather than corporates (high spreads).
For investors preferring a single holding, an aggregate fund or intermediate fund (like VGIT) approximates a ladder's behavior without the effort.
Time horizon and duration allocation
An investor's time horizon should drive duration allocation:
Under 3 years to need principal: Short-term bonds (1-3 year duration). Ensures principal is available without interest rate loss.
3-10 years to need principal: Intermediate bonds (4-6 year duration). Captures meaningful yield while avoiding excessive volatility. A retiree with 10 years of planned spending might hold all intermediate bonds.
10+ years to retirement: Intermediate and long-term mix. A young investor might hold 70% intermediate / 30% long, capturing the higher long-term yield while maintaining reasonable stability.
20+ years to retirement: Intermediate and long-term mix, tilted toward long. A 25-year-old can afford long-term duration; if rates rise and bonds fall, they have decades to wait for recovery. The extra yield from longer bonds compounds significantly.
Rebalancing and rate view alignment
Most investors should rebalance between duration buckets annually or when allocations drift significantly. If long-term bonds have rallied and now represent 40% instead of 30% of the portfolio, trim them back to 30%, reinforcing the plan.
However, some investors intentionally overweight or underweight based on rate expectations. If you believe rates will fall, overweight long-term bonds. If you believe rates will rise, overweight short-term bonds. This requires conviction and discipline (and often, wrong timing).
Most investors should avoid this timing. Maintaining a steady allocation regardless of rate expectations is more reliable.
Costs and tax efficiency
Short-term bonds have lower turnover (they mature in 1-3 years, requiring reinvestment). Long-term bonds have lower turnover (held for decades). Intermediate bonds are in the middle. For buy-and-hold investors, turnover is less important than total return. For tax-efficient investors, short and long bonds are slightly better (lower realized gains) than intermediate bonds (which turn over faster).
Next
This chapter has covered the mechanics of bond funds and ETFs, the major fund categories (Treasuries, corporates, munis, international, emerging markets), and duration strategy. With this foundation, an investor can construct a diversified bond portfolio tailored to their time horizon, risk tolerance, and tax situation. The next chapter shifts to using bonds strategically within a total portfolio alongside stocks.