Fixed-Income ETFs and the Short End of the Curve: How SGOV and Cash-Management Treasury ETFs Work

Educational content only. This article is not investment advice and is not a recommendation to buy, sell, or hold SGOV or any other fund named below.

Over the past few years, a specific corner of the fixed-income ETF market — funds that hold Treasury bills with maturities measured in weeks or months, not years — has grown into some of the largest exchange-traded funds in the country. The largest of these, the iShares 0-3 Month Treasury Bond ETF (ticker SGOV), had grown to roughly $98.5 billion in assets as of mid-July 2026, putting it within reach of becoming the first fund in its category to cross $100 billion (ETF.com — SGOV Nears $100 Billion, a First for Ultra-Short Bond ETFs). Investors reach for these funds mainly to hold cash-like balances inside a brokerage account — money earmarked for near-term spending, sitting between trades, or set aside as a buffer — rather than to make a long-term bet on interest rates.

This article explains, in general and educational terms, how that category of fund works: where it sits on the broader fixed-income spectrum, what the individual funds actually hold, why their share prices move in a distinctive monthly pattern, and the tax and risk mechanics worth understanding before researching any of them further. It does not evaluate whether any of these funds — or holding cash in a brokerage account at all, versus a bank account, money market fund, or CD — is the right choice for any individual. That depends on a person's own liquidity needs, tax situation, and risk tolerance, which is not something a general-education article, or Zydhra as a platform, is positioned to assess.

Where the short end sits on the fixed-income spectrum

"Fixed income" broadly describes securities that pay a scheduled stream of interest and return a stated principal amount at maturity — bonds, notes, and bills issued by governments, agencies, and corporations. A fixed-income ETF pools many such securities into a single, exchange-traded fund, so an investor buys one security (a fund share) rather than assembling and managing a portfolio of individual bonds.

Within that universe, the funds this article focuses on sit at the very short end of the U.S. Treasury market — securities the U.S. Department of the Treasury issues with the shortest maturities and, in the case of floating-rate notes, an interest rate that resets rather than staying fixed. Moving outward along the curve, in increasing order of typical interest-rate sensitivity:

Ultra-short Treasury / T-bill funds (SGOV, BIL, SHV) — hold Treasury bills maturing in roughly zero to twelve months, with SGOV and BIL concentrated in the shortest end of that range.
Short-term Treasury funds (SHY, VGSH) — hold Treasury notes maturing in roughly one to three years.
Floating-rate Treasury funds (USFR, TFLO) — hold Treasury floating rate notes (FRNs), a security type whose interest payment resets periodically rather than staying fixed for the life of the note.
Ultra-short bond funds (ICSH, JPST, MINT) — hold a mix of short-maturity government, agency, and investment-grade corporate debt rather than Treasuries exclusively.
Broad "aggregate" bond funds (for example AGG or BND) — hold thousands of Treasury, agency, mortgage-backed, and investment-grade corporate bonds across a wide range of maturities, giving them a duration typically measured in several years rather than months (iShares — AGG Fact Sheet (PDF); Vanguard — BND fund page).
Long-term Treasury funds (for example TLT) — hold Treasury bonds with maturities of 20 years or more, giving them a substantially longer duration — and correspondingly greater price sensitivity to interest-rate changes — than any fund discussed above (iShares — TLT fund page).

How this differs from a money market fund. Ultra-short Treasury ETFs are frequently compared to money market funds because both are commonly used to hold cash-like balances, but they are structured differently. Most money market funds — a separate, older category of mutual fund regulated under its own SEC rules — seek to maintain a stable net asset value of $1.00 per share, and can be bought or redeemed directly through the fund at that stable price (Investor.gov — Money Market Funds Investor Bulletin; Investor.gov — Money Market Funds). A fund like SGOV, by contrast, is an ETF: its share price is marked to market and trades on an exchange throughout the day like a stock, and — as described below — its price is not designed to hold steady at a fixed number; it accrues value daily and then drops when it makes a distribution. Neither structure is FDIC-insured or guaranteed, a point covered in more detail in the risks section below.

The T-bill / ultra-short Treasury group: SGOV, BIL, SHV

These three funds are the most concentrated at the very short end of the curve, and they're often discussed together because their holdings and behavior are similar, even though they're run by different issuers.

SGOV — iShares 0-3 Month Treasury Bond ETF. SGOV seeks to track the ICE 0-3 Month US Treasury Securities Index, holding Treasury bills with remaining maturities of roughly zero to three months. As of its fact sheet dated June 30, 2026, the fund reported a weighted average maturity of about 0.09 years (roughly one month), an expense ratio of 0.09%, and a 30-day SEC yield of 3.54% (iShares — SGOV Fact Sheet (PDF), as of June 30, 2026; iShares — SGOV fund page). That short a maturity means the fund's holdings are turning over constantly, and its interest-rate sensitivity (duration) is close to zero — a small change in interest rates has very little effect on the fund's share price, though it does change how much interest the fund earns going forward.

BIL — SPDR Bloomberg 1-3 Month T-Bill ETF. BIL tracks the Bloomberg 1-3 Month U.S. Treasury Bill Index, holding Treasury bills with remaining maturities between roughly one and three months. Per its own fact sheet, BIL's gross expense ratio is approximately 0.14% (State Street Global Advisors — BIL Fact Sheet (PDF); State Street Global Advisors — BIL fund page). Structurally, BIL is close to SGOV — both hold a rolling basket of very short Treasury bills — though the two funds track different index rules and are run by different asset managers (BlackRock for SGOV, State Street for BIL).

SHV — iShares 0-1 Year Treasury Bond ETF. SHV (marketed by iShares as the "0-1 Year Treasury Bond ETF," and still trading under the ticker SHV) holds Treasury bills and notes with remaining maturities of one year or less — a slightly wider maturity band than SGOV or BIL. Its expense ratio is 0.15% per its own materials (iShares — SHV fund page). Because it can hold securities out to a full year, SHV's duration runs modestly longer than SGOV's or BIL's, though still short in absolute terms compared with anything discussed further down this article.

All three funds share the same basic credit exposure: they hold direct obligations of the U.S. Treasury, not corporate or agency debt, which — as covered in the tax section below — has a specific tax consequence at the state level.

Moving out the curve: short-term Treasury funds (SHY, VGSH)

Stepping slightly further out the maturity spectrum introduces more interest-rate sensitivity, which is a useful concept to understand before comparing any bond fund to another.

SHY — iShares 1-3 Year Treasury Bond ETF holds Treasury notes with remaining maturities of roughly one to three years. Its expense ratio is 0.15%, and its effective duration has run in the neighborhood of two years, reflecting that maturity band (iShares — SHY Fact Sheet (PDF); iShares — SHY fund page).

VGSH — Vanguard Short-Term Treasury ETF tracks the Bloomberg U.S. Treasury 1-3 Year Bond Index and, as of its fact sheet dated June 30, 2026, reported an average duration of 1.9 years and an expense ratio of 0.03% (Vanguard — VGSH Fact Sheet (PDF), as of June 30, 2026; Vanguard — VGSH fund page).

Duration, in plain terms, is a measure of how sensitive a bond fund's price is to a change in interest rates — the U.S. Securities and Exchange Commission's own investor materials describe it as a measure that accounts for a security's interest payments as well as its time to maturity, and note that funds with longer average durations generally can be expected to be more sensitive to interest-rate changes than funds with shorter durations (Investor.gov — Investor Bulletin: Fixed Income Investments — When Interest Rates Go Up, Prices of Fixed-Rate Bonds Fall). A fund like SHY or VGSH, with roughly a two-year duration, will see more price movement from a given change in interest rates than SGOV or BIL — but far less than a fund holding 20-year Treasury bonds. That is a structural, mechanical relationship, not a prediction about which way rates will move next.

Floating-rate Treasury funds: USFR and TFLO

A different way to manage interest-rate sensitivity is to hold securities whose interest payment itself resets, rather than staying fixed until maturity. The U.S. Treasury issues Floating Rate Notes (FRNs), currently auctioned as 2-year notes, whose interest rate is the sum of an index rate — tied to the most recently auctioned 13-week Treasury bill's discount rate, reset weekly since 13-week bills are auctioned every week — plus a fixed spread set at the FRN's own auction (TreasuryDirect — Floating Rate Notes (FRNs); TreasuryDirect — Frequently Asked Questions on Floating Rate Notes). Interest accrues daily on the note's par value at that reset rate.

USFR — WisdomTree Floating Rate Treasury Fund and TFLO — iShares Treasury Floating Rate Bond ETF both hold portfolios of these Treasury FRNs. Because the coupon resets frequently rather than staying fixed, both funds carry very low interest-rate sensitivity despite holding notes with a stated (final) maturity of up to two years — the weekly reset largely offsets the price effect that a fixed-rate note of the same maturity would otherwise show when rates move (iShares — Mechanics of U.S. Treasury Floating Rate Notes (PDF)). As of their own materials, USFR's expense ratio is 0.15% (WisdomTree — USFR fund page; WisdomTree — USFR Fact Sheet (PDF)) and TFLO's expense ratio is also 0.15% (iShares — TFLO fund page; iShares — TFLO Fact Sheet (PDF)).

The practical distinction from SGOV, BIL, or SHV: those funds achieve low duration by holding securities that mature very soon, so the whole portfolio is constantly rolling over into new bills at current rates. USFR and TFLO instead hold notes with a longer stated maturity but a coupon that resets on its own schedule — a different mechanical route to a similar outcome of low price sensitivity to rate changes.

Ultra-short bond funds: a small step into credit risk (ICSH, JPST, MINT)

A third group looks similar on the surface — short average maturities, monthly or more frequent distributions — but differs in one important respect: these funds don't limit themselves to U.S. Treasuries. They add investment-grade corporate debt, commercial paper, certificates of deposit, and other short-term credit instruments, which introduces a modest amount of credit risk (the risk that a bond issuer fails to pay) that a pure Treasury fund doesn't carry.

ICSH — iShares Ultra Short Duration Bond Active ETF. An actively managed fund (meaning a manager selects holdings rather than tracking a fixed index), ICSH invests in investment-grade, U.S.-dollar-denominated fixed- and floating-rate debt with an ultra-short duration target. Its expense ratio is 0.08% per its own fact sheet (iShares — ICSH Fact Sheet (PDF); iShares — ICSH fund page).

JPST — JPMorgan Ultra-Short Income ETF. Also actively managed, JPST seeks current income while aiming to keep principal volatility low, investing in investment-grade, dollar-denominated fixed- and floating-rate debt. Corporate-backed debt — including corporate bonds, commercial paper, and certificates of deposit — has typically made up 65% to 90% of the fund's assets, and stood at roughly 76% as of March 2026, according to the fund's own materials; its expense ratio is 0.18% (J.P. Morgan Asset Management — JPST Fact Sheet (PDF), May 31, 2026; J.P. Morgan Asset Management — JPST fund story (PDF)).

MINT — PIMCO Enhanced Short Maturity Active ETF. MINT seeks maximum current income consistent with preservation of capital and daily liquidity, investing across a diversified mix of short-maturity fixed-income instruments; PIMCO's own materials state the fund's average portfolio duration will normally not exceed one year and varies with the manager's own market outlook. Its net expense ratio is 0.36% (PIMCO — MINT fund page).

The general trade-off across this group, described here in purely structural terms: by adding corporate, bank, and other private-issuer debt alongside (or instead of) Treasuries, these funds take on some credit risk and, in less liquid market conditions, some liquidity risk that a pure T-bill fund like SGOV, BIL, or SHV does not carry to the same degree. The SEC has published investor guidance specifically flagging this distinction for the broader ultra-short bond fund category, noting that such funds can carry different — and in some cases higher — risks than money market funds or CDs, and urging investors to understand a fund's specific holdings and duration before treating it as a cash-equivalent (Investor.gov — Ultra-Short Bond Funds: Know Where You're Parking Your Money). That is a description of a structural risk category, not a statement about how any specific fund named above has performed or will perform.

How these funds actually behave: the monthly "sawtooth" pattern

One behavior of ultra-short Treasury ETFs surprises investors who are used to watching a stock chart: rather than moving randomly day to day, a fund like SGOV's share price tends to rise steadily through most of the month and then drop sharply on a single day, repeating that cycle every month — a pattern commonly described as a "sawtooth" (The Peculiar Behavior of Short-Term Treasury ETF Prices).

The mechanic behind it is straightforward. These funds accrue interest on their Treasury holdings daily, and that accrued-but-not-yet-paid interest is reflected in the fund's rising net asset value (NAV) throughout the month. Once a month, the fund distributes that accrued interest to shareholders in cash — and on the ex-dividend date (the date on or after which a new buyer is no longer entitled to that particular distribution), the fund's share price drops by an amount that closely tracks the size of the distribution being paid out (Investor.gov — Glossary: Ex-Dividend Date; The Peculiar Behavior of Short-Term Treasury ETF Prices). The value hasn't disappeared — it has simply moved from "unrealized, sitting in the share price" to "a cash distribution paid to whoever owned shares before the ex-dividend date."

This is worth stating plainly because it's a common point of confusion: the drop at month-end is not a discount, and buying shares right after the drop is not "buying the dip" in the sense that term is usually used for a stock. Before the drop, a share is worth more but comes with an imminent taxable distribution attached; after the drop, a share is worth less but that distribution has already been separated out. Structurally, buying immediately before the drop and receiving that distribution, versus buying immediately after the drop and not receiving it, are close to economically equivalent on a pre-tax basis — the total value (share price plus the distribution received or not received) is approximately the same either way. This is a mechanical description of how the fund's distribution schedule interacts with its share price, not a timing strategy, and it does not change the fund's underlying yield.

One place the distribution schedule has a mechanical tax effect — and only in a taxable (non-retirement) brokerage account — is the timing of a first purchase. A cash distribution from one of these funds is generally taxable income in the year it's paid, regardless of how briefly the buyer held the shares before receiving it. Because of that, buying shares immediately after an ex-dividend date — rather than immediately before one — means a new buyer's first distribution reflects only the interest that accrues after their purchase, rather than immediately triggering a taxable payment that includes interest accrued (and reflected in the price) before they owned the shares at all. In isolation this effect is small — it reflects only the interest accrued over the few days around the distribution date — and does not by itself justify timing an otherwise-planned purchase around a fund's distribution schedule. This is a general observation about when taxable income is recognized in a specific type of account, not a suggestion about whether or when to buy — the tax effect (if any) depends on an investor's account type, holding period, tax bracket, and overall situation, and anyone weighing it should consult a qualified tax professional.

Concepts worth understanding before comparing any of these funds

SEC 30-day yield vs. distribution yield vs. 7-day yield. Fund yield figures are not all calculated the same way, and mixing them up leads to apples-to-oranges comparisons. - The 30-day SEC yield is a standardized figure the SEC requires funds to calculate using a specific formula: net investment income earned over the trailing 30 days, annualized, and divided by the fund's share price — a methodology designed so a given percentage means the same thing across different fund companies (Fidelity Institutional — Understanding Money Market and Bond Fund Terminology (PDF)). - The 7-day yield is the money-market-fund-specific convention, using the same basic idea over a trailing seven-day window instead of thirty, and is the figure most commonly quoted for money market funds specifically (SEC.gov — Money Market Funds 7-Day Yields (data visualization); Fidelity Institutional — Understanding Money Market and Bond Fund Terminology (PDF)). - A trailing distribution yield simply totals what a fund actually paid out over some past period (often the trailing 12 months) divided by its current price — a backward-looking figure that can differ from both SEC yield calculations, especially when rates have been changing.

None of these figures is a projection, and none guarantees what a fund will pay going forward — past distributions and past yields do not predict future distributions or future yields, and any of these numbers can change from one month to the next as short-term interest rates move.

Duration and interest-rate risk, described above, is the reason SGOV's price barely moves when rates change while TLT's can move substantially — a structural characteristic tied to how far out the maturity curve a fund's holdings sit, not a judgment about which is preferable for any individual.

Credit risk is the risk that a bond's issuer fails to make a promised payment. U.S. Treasury securities are backed by the full faith and credit of the U.S. government and carry no meaningful credit risk in the way a corporate bond does; funds that add corporate, bank, or other private-issuer debt (the ICSH/JPST/MINT group above) take on some amount of that risk in exchange for a potentially different yield profile.

Expense ratios are the fund's annual operating cost, expressed as a percentage of assets and deducted from fund assets over time rather than billed separately; they are a direct, arithmetic drag on a fund's return relative to its gross yield, all else equal, though they don't capture brokerage commissions or bid-ask spreads an investor may separately incur.

The tax angle: Treasury interest and the state/local exemption. Interest paid on direct U.S. Treasury obligations — bills, notes, bonds, TIPS, and FRNs — is subject to federal income tax but is exempt from state and local income tax under federal law (TreasuryDirect — Tax Forms and Tax Withholding; IRS — Topic no. 403, Interest received). That exemption generally passes through to fund shareholders in proportion to how much of a fund's income actually comes from qualifying U.S. government obligations, and each fund publishes that percentage annually. As one illustration: for the 2024 tax year, iShares' annual "U.S. Government Source Income Information" reported that roughly 97.53% of SGOV's distributed income qualified as U.S. government obligation interest (iShares — 2024 U.S. Government Source Income Information (PDF); plain-English overview at My Money Blog). Some states set a minimum qualifying-income threshold before shareholders may exclude a fund's Treasury-derived interest, and the exact threshold and mechanics vary by state — some, for example, test the fund's holdings at each quarter-end rather than on an annual average — so whether any given fund's percentage clears a particular state's rule must be confirmed against that state's own tax guidance. A fund that mixes in corporate, agency, or mortgage-backed debt — such as the ultra-short bond funds or a broad aggregate bond fund discussed above — generally reports a meaningfully lower qualifying percentage, because only the Treasury-derived portion of its income qualifies for the exclusion. This percentage is recalculated every year and varies by fund; investors who want to claim this exclusion should check the specific, current-year figure the fund publishes (typically in a "U.S. Government Source Income" or similar document) and consult a tax professional about how it applies to their own return, since state rules and thresholds vary.

Risks and caveats

The following is general, structural information about this category of fund — not a complete list of risks, and not a substitute for reading a fund's own prospectus, which contains its full, legally required risk disclosures.

Not FDIC-insured, not guaranteed. Like any mutual fund or ETF, none of the funds discussed in this article is insured or guaranteed by the FDIC or any other government agency, and none is a bank deposit — a fund's value can fluctuate, and it's possible to lose money, even in a fund holding only U.S. Treasuries (Investor.gov — Money Market Funds).
NAV can dip, even for very short-duration Treasury funds. While these funds' near-zero duration limits how much their price moves from interest-rate changes, it does not eliminate price movement entirely, and unusual market conditions can still affect a fund's share price relative to its underlying holdings.
Yields move with short-term interest rates, in both directions. The yields quoted throughout this article are point-in-time figures as of the dates cited. Because these funds hold very short-maturity instruments that roll over constantly, their yields tend to track prevailing short-term rates closely and can rise or fall relatively quickly if the Federal Reserve changes its target rate — a mechanical relationship, not a forecast of what rates will do next.
Ultra-short bond funds carry credit and liquidity risk a pure T-bill fund doesn't. As described above and flagged specifically by the SEC's own investor guidance on this fund category, funds that hold corporate, bank, or other private-issuer debt are exposed to the possibility that an issuer's credit quality deteriorates or that a security becomes harder to sell at its expected value during stressed market conditions — risks that a fund holding only U.S. Treasuries is not exposed to in the same way (Investor.gov — Ultra-Short Bond Funds: Know Where You're Parking Your Money).
Past performance does not guarantee or predict future results. Nothing about any fund's expense ratio, current yield, size, or historical price pattern says anything about how it will perform, yield, or behave going forward.

Closing note

The funds discussed in this article span a specific, short-duration slice of the U.S. fixed-income market, from Treasury bills maturing in weeks to Treasury notes maturing in a few years, with a floating-rate and a modest-credit variant along the way. Understanding how each is built — what it holds, how its duration is achieved, why its share price moves in a predictable monthly pattern, and how the state-tax treatment of Treasury income does or doesn't pass through — is useful groundwork for anyone researching this part of the market. It is not, and isn't meant to be, a conclusion about which fund, if any, fits a particular person's cash management needs; that depends on an individual's liquidity needs, tax situation, account type, and risk tolerance, and is a question for that person, or a licensed financial or tax professional working with them, to work through directly.

Disclaimer: This article is for general educational and informational purposes only. It is not investment advice, and nothing in it should be construed as a recommendation to buy, sell, or hold SGOV, BIL, SHV, SHY, VGSH, USFR, TFLO, ICSH, JPST, MINT, AGG, BND, TLT, or any other fund or security discussed above. Zydhra is a portfolio-tracking and analytics tool — it is not a broker-dealer and is not a registered investment adviser. Expense ratios, yields, durations, holdings, assets under management, and tax-exempt-income percentages discussed above change over time and were current as of the dates and sources cited; they will likely be different by the time you read this, and none of these figures is a projection or guarantee of future performance. Past performance and past yields do not guarantee or predict future results. Tax treatment depends on an individual's specific circumstances, account type, and state of residence, and can change; nothing here is tax advice. Before making any investment or tax decision, review the relevant fund's official prospectus in full and consult a licensed financial or tax professional.