Old Westbury Municipal Bond Fund
Actively managed U.S. bond fund
As of its 2026 Q2 report, Old Westbury Municipal Bond Fund held 551 positions with $4.54B in net assets. Its ten largest holdings made up 7.6% of the fund. The OWMBX share class costs 0.57% a year. Over the 12 months to May 2026, OWMBX returned 4.3%, with dividends reinvested. In 2026 Q3 it added 47 new positions and exited 55.
The Funds goal is to seek total return (consisting of current income that is exempt from regular federal income tax and capital appreciation).
The fund invests primarily in investment-grade municipal securities issued by U.S. states, territories, and political subdivisions, with at least 80% of assets in federal-tax-exempt debt. The fund may also use futures and options to enhance returns or hedge interest rate risk, and may hold ETFs, Treasury securities, taxable municipals, and inflation-protected securities. Because returns depend on the credit quality and price movements of the municipal securities selected, performance will vary with municipal bond market conditions and issuer credit events.
What you own
| Company | Weight | Value | Shares |
|---|---|---|---|
FEDERATED HERMES MONEY MARKET OBLIGATIONS TRUST | 2.80% | $127.20M | — |
DENVER (CO), CITY AND COUNTY OF 5.00% · due 2028-12-01 | 0.64% | $29.15M | — |
BROOKHAVEN GA DEV AUTH 4.00% · due 2044-07-01 | 0.59% | $27.02M | — |
WASHINGTON ST 5.00% · due 2042-08-01 | 0.59% | $26.87M | — |
NEW YORK N Y 4.12% · due 2026-08-01 | 0.55% | $25.01M | — |
WASHINGTON ST 5.00% · due 2035-02-01 | 0.50% | $22.80M | — |
NEW HAMPSHIRE HEALTH AND EDUCATIONAL FACILITIES AUTHORITY (NH) 5.00% · due 2032-06-01 | 0.50% | $22.60M | — |
NEW YORK STATE URBAN DEVELOPMENT CORP (NY) 5.00% · due 2036-03-15 | 0.49% | $22.49M | — |
WASHINGTON ST 5.00% · due 2037-08-01 | 0.49% | $22.29M | — |
NEW JERSEY EDUCATIONAL FACILITIES AUTHORITY (NJ) 5.00% · due 2036-03-01 | 0.47% | $21.43M | — |
The 200 largest of 551 holdings, with the share counts as filed, open with a free account.
What the fund is made of
Percentages are of fund net assets. Rounding, liabilities and short positions can make totals differ from 100%.
| Bonds | 97.26% |
| Cash & short-term | 2.80% |
How it has done
OWMBX share class · total returns with dividends reinvested
Volatility over the last 12 months: 2.88%. Past returns are a record, not a forecast.
Jun 2026 and Jul 2026 have been filed since the trailing figures were struck, so they are not in the table above or the curve — every figure here shares one cut-off, which is what makes them comparable with other funds.
Fees & fund details
Old Westbury Municipal Bond Fund is an actively managed U.S. bond fund.
- Asset class
- Bonds
- Region
- United States
- Management
- Actively managed
- Fund type
- Open-end fund
- Credit quality
- Investment grade
- Rate sensitivity
- Intermediate duration
- Expense ratio, by class
- 0.57%· OWMBX 0.57%
- Portfolio turnover
- 52.00% a year · as of 2026 Q1
Net is what a holder pays after the adviser's contractual waiver; gross is before it. A waiver can expire.
Turnover is how much of the portfolio was replaced in a year.
Classified from what the fund holds, not from its name · 2026 Q2. The summary is a paraphrase of the prospectus; the objective is verbatim.
What changed this quarter
Positions that entered or left the fund since its previous filing. Positions that were only resized are not listed.
47 new· the largest 5
55 exited· the largest 8
Debt profile
What this fund holds — value-weighted across its bond and securitized long positions · as of 2026-04-30
Share of the fund's debt by how its coupon behaves — the fact that decides whether a rate move reaches this portfolio at all.
| Fixed rate | 98.2% |
| Floating rate | 1.5% |
| Zero-coupon or unclassified | 0.3% |
Share of the fund's debt value in each maturity band, shortest first.
| <1y | 9.2% |
| 1-3y | 13.9% |
| 3-5y | 17.0% |
| 5-10y | 42.5% |
| 10y+ | 17.4% |
Based on what filers reported; a filer that never reported a flag also reads as none.
Risk profile
Interest-rate and credit-spread sensitivity, both in years · as of 2026Q2
More of this fund’s sensitivity sits in credit spreads than in interest rates — a rate rally that comes with a credit selloff works against it.
Where the loss would come from. The two shocks are the same size, so this is the balance of the fund's two sensitivities rather than a bet on one moving more.
| Credit spreads | 50% |
| Interest rates | 50% |
Filers report the impact of a 0.01% move only, so the total is our own scaling of that one number and overstates the loss on most bonds — read it as approximate, never as precise. The two sensitivities overlap rather than add up: they measure the same positions against different shocks, which is why the durations above are shown side by side and never summed.
Share of the fund's spread duration carried by each credit tier.
| Investment grade | +4.62 yr |
Share of duration at each point, shortest first. A positive figure loses value when spreads widen; a negative one offsets — a credit hedge.
| 3 mo | 0.03 yr | 1% |
| 1 yr | 0.48 yr | 11% |
| 5 yr | 2.15 yr | 47% |
| 10 yr | 1.75 yr | 38% |
| 30 yr | 0.14 yr | 3% |
| 3 mo | 0.02 yr | 0% |
| 1 yr | 0.44 yr | 9% |
| 5 yr | 2.73 yr | 59% |
| 10 yr | 1.43 yr | 31% |
| 30 yr | 0.01 yr | 0% |
The two bands measure the same positions against different shocks and do not add — a Treasury carries rate duration and no spread duration, a floating-rate credit the reverse. Rate tenors are also summed across every currency the fund discloses.
Show the numbers
| Tenor | Rate yrs | IG yrs | HY yrs | IG $/bp | HY $/bp |
|---|---|---|---|---|---|
| 3 mo | +0.03 | +0.02 | +0.00 | $9.5k | $0 |
| 1 yr | +0.48 | +0.44 | +0.00 | $198.4k | $0 |
| 5 yr | +2.15 | +2.73 | +0.00 | $1.24m | $0 |
| 10 yr | +1.75 | +1.43 | +0.00 | $647.7k | $0 |
| 30 yr | +0.14 | +0.01 | +0.00 | $3.5k | $0 |
Dollar change per 1bp of spread movement, as filed and sign-anchored. A blank cell was not filed; a zero was.
A newer credit-spread reading (2026Q3) is on file. This page holds one quarter across every figure on it, so that one appears here next quarter.
Understand how this fund fits with the rest.
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