BBMUX — Bridge Builder Municipal Bond Fund
Data updated: 2026-10-28
BBMUX — Bridge Builder Municipal Bond Fund. 0.12% expense ratio · since 2015 · Intermediate Municipal Bond. Holdings, fees, performance and SEC filings.
BBMUX Fund Overview
BBMUX — Bridge Builder Municipal Bond Fund is a US mutual fund managed by Olive Street Investment Advisers LLC, categorised as Intermediate Municipal Bond. Its benchmark is the Bloomberg Barclays Municipal Bond (Returns Universe). ABC INVEST provides holdings, performance, costs, cashflows, risk data, prospectus documents and SEC filings, sourced from SEC filings.
- Type: US mutual fund
- Adviser: Olive Street Investment Advisers LLC
- Sub-advisers: Blackrock Investment Management, LLC, Fiam, LLC, MacKay Shields LLC and Robert W. Baird and Co., Inc.
- Trust: Bridge Builder Trust
- Category: Intermediate Municipal Bond
- Minimum investment: no minimum
- Additional investment: no minimum
- Benchmark: Bloomberg Barclays Municipal Bond (Returns Universe)
- Inception date: September 14, 2015
- Assets under management: $20,787,412,375
- 1-year return: 6.3%
- Ticker: BBMUX
- SEC CIK: 0001567101
- SEC series ID: S000050632
- Share class ID: C000159840
- FIGI: BBG009L21PQ7
- LEI: 5493003VPO8RCMPVYN16
About BBMUX
Bridge Builder Municipal Bond Fund (BBMUX) seeks current income exempt from federal tax. It invests at least 80% of its net assets, plus any borrowings for investment purposes, in municipal securities whose interest is generally exempt from federal income tax, including some bonds subject to the Federal AMT and some below investment grade bonds. The fund is managed by multiple sub-advisers, including BlackRock, FIAM, T. Launched September 14, 2015, BBMUX costs 0.12% a year net (0.38% gross less a 0.26% fee waiver) and returned 6.3% in the 12 months to June 30, 2026, based on monthly returns reported to the SEC on Form N-PORT, with 3.5% volatility.
BBMUX Holdings
Top 10 holdings of Bridge Builder Municipal Bond Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| Fidelity Inv Mmkt Govt-Inst | 0.94% |
| Southeast Energy A 5% 10/01/30 | 0.46% |
| Kentucky St Publi V/r 01/01/55 | 0.37% |
| California Cmnty V/r 01/01/55 | 0.29% |
| Puerto Rico SA 4.329% 07/01/40 | 0.28% |
| Miami-Dade Cnty Fl 5% 10/01/32 | 0.26% |
| Chicago Il Brd of 6% 04/01/46 | 0.26% |
| Main Street Energy 5% 10/01/33 | 0.25% |
| Black Belt Energy 5% 11/01/36 | 0.24% |
| Univ of Texas Tx V/r 08/01/56 | 0.24% |
BBMUX Portfolio Allocation
Asset-class allocation of Bridge Builder Municipal Bond Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Fixed Income | 96.2% |
| Securitized | 1.5% |
| Cash & Equivalents | 1.0% |
BBMUX Performance
Total returns for BBMUX through June 2026, from SEC filings.
| Period | Total return |
|---|---|
| YTD | 1.93% |
| 1 year | 6.30% |
| 3 years (annualised) | 4.27% |
| 5 years (annualised) | 1.51% |
BBMUX Risk Information
Risk metrics for BBMUX, derived from monthly returns in SEC filings.
- 1-year volatility (annualised): 3.48%
BBMUX Costs and Fees
BBMUX costs about $12 per $10,000 invested per year in fund expenses.
- Net expense ratio: 0.12%
- Gross expense ratio: 0.38%
- Portfolio turnover: 23%
- Brokerage commissions: 0.00 bps of average net assets (SEC N-CEN)
BBMUX Cashflows
Over the 12 months to 2026-06, Bridge Builder Municipal Bond Fund had net inflows of $3,088,499,123, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-06 | $471,736,152 |
| 2026-05 | $111,005,281 |
| 2026-04 | −$153,732,166 |
| 2026-03 | $292,972,666 |
| 2026-02 | $378,720,472 |
| 2026-01 | $379,658,580 |
BBMUX Debt Constituents
Largest debt holdings of Bridge Builder Municipal Bond Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Debt holding | % of net assets |
|---|---|
| Southeast Energy A 5% 10/01/30 | 0.46% |
| Kentucky St Publi V/r 01/01/55 | 0.37% |
| California Cmnty V/r 01/01/55 | 0.29% |
| Puerto Rico SA 4.329% 07/01/40 | 0.28% |
| Miami-Dade Cnty Fl 5% 10/01/32 | 0.26% |
| Chicago Il Brd of 6% 04/01/46 | 0.26% |
| Main Street Energy 5% 10/01/33 | 0.25% |
| Black Belt Energy 5% 11/01/36 | 0.24% |
| Univ of Texas Tx V/r 08/01/56 | 0.24% |
| Tennessee St Energ 5% 12/01/35 | 0.24% |
BBMUX Prospectus and SEC Filings
Official Bridge Builder Municipal Bond Fund filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.
- Prospectus (485BPOS) — filed 2026-10-28
- Prospectus (485BPOS) — filed 2025-10-27
- Prospectus (485BPOS) — filed 2024-10-25
- Portfolio holdings (N-PORT) — filed 2026-08-26
- Portfolio holdings (N-PORT) — filed 2026-05-22
- Portfolio holdings (N-PORT) — filed 2026-02-23
- Annual census (N-CEN) — filed 2026-09-11
- Annual census (N-CEN) — filed 2025-09-11
BBMUX Service Providers
Firms that manage, distribute, hold, administer and audit Bridge Builder Municipal Bond Fund, as reported on SEC Form N-CEN, fiscal year ending June 30, 2026.
- Adviser: Olive Street Investment Advisers LLC
- Sub-advisers: Blackrock Investment Management, LLC, Fiam, LLC, MacKay Shields LLC and Robert W. Baird and Co., Inc.
- Distributor: Alps Distributors, Inc.
- Custodian: Brown Brothers Harriman and Co.
- Transfer agent: Alps Fund Services, Inc.
- Administrator: Brown Brothers Harriman & Co.
- Auditor: Pricewaterhousecoopers Llp
Related Funds
Other Intermediate Municipal Bond funds tracked on ABC INVEST:
BBMUX: Frequently Asked Questions
What is the expense ratio of Bridge Builder Municipal Bond Fund (BBMUX)?
BBMUX has a net expense ratio of 0.12%, about $12 a year for every $10,000 invested. That is after a 0.26% fee waiver on a gross ratio of 0.38%. BBMUX fees and costs
What is the minimum investment for BBMUX?
BBMUX has no minimum initial investment, and there is no minimum for additional purchases. Source: the fund's prospectus (October 2026).
What is BBMUX's benchmark?
BBMUX measures its performance against the Bloomberg Barclays Municipal Bond (Returns Universe).
What are BBMUX's top holdings?
As of June 30, 2026, BBMUX held 5,793 positions. The largest are Fidelity Inv Mmkt Govt-Inst (0.94%), Southeast Energy A 5% 10/01/30 (0.46%), Kentucky St Publi V/r 01/01/55 (0.37%), California Cmnty V/r 01/01/55 (0.29%) and Puerto Rico SA 4.329% 07/01/40 (0.28%). All BBMUX holdings
Can I download the full list of BBMUX holdings?
Yes. The complete BBMUX holdings list as of June 30, 2026 can be downloaded as a CSV file from the Holdings page: holding, ticker, FIGI, sector, country, asset type, shares, value and share of net assets, from the fund's SEC N-PORT filing. Download BBMUX holdings (CSV)
How has Bridge Builder Municipal Bond Fund performed?
BBMUX returned +6.3% over the 12 months to June 2026, +4.3% a year over 3 years and +1.5% a year over 5 years. BBMUX performance and risk
How large is BBMUX?
BBMUX manages $20,787,412,375 (SEC N-PORT, June 2026). Investors added a net $3,088,499,123 over the past 12 months.
Who manages BBMUX and when did it launch?
BBMUX is managed by Olive Street Investment Advisers LLC, with Blackrock Investment Management, LLC, Fiam, LLC, MacKay Shields LLC and Robert W. Baird and Co., Inc. as sub-advisers. It is a series of Bridge Builder Trust. It launched on September 14, 2015.
How does BBMUX compare with similar Intermediate Municipal Bond funds?
Among 209 Intermediate Municipal Bond funds with $100,000,000+ in assets, BBMUX ranks #18 of 209 on net expense ratio (0.12%) and #5 of 209 by assets. The largest is Vanguard Intermediate-Term Tax-Exempt Fund (VWIUX). Compare BBMUX with VWIUX
Where can I find BBMUX's prospectus and SEC filings?
BBMUX's latest prospectus (485BPOS) was filed October 28, 2026 and its latest N-PORT holdings report was filed August 26, 2026. All 49 filings are linked on ABC INVEST and on SEC EDGAR (series S000050632). BBMUX SEC filings
Data Sources
ABC INVEST compiles this page from public filings made to the U.S. Securities and Exchange Commission (SEC) through EDGAR: portfolio holdings and monthly cashflows from Form N-PORT, expenses and returns from fund prospectuses (Form 485BPOS) and the SEC DERA Risk/Return Summary data sets, and annual data from Form N-CEN.
For information only. Not investment advice: figures are as reported in SEC filings and may contain errors or be out of date. Past performance does not guarantee future results.