MCBMX — MFS Core Bond Fund
Data updated: 2026-07-13
MCBMX — MFS Core Bond Fund data: holdings, portfolio allocation, expenses, performance, cashflows, risk and SEC filings. Long Total / Aggregate Bond · $33.80M AUM · 0.33% expense ratio · 4.3% 1-yr return. From SEC regulatory filings.
MCBMX Fund Overview
MCBMX — MFS Core Bond Fund is a US mutual fund managed by Mfs Series Trust XII, categorised as Long Total / Aggregate Bond. ABC INVEST provides holdings, performance, costs, cashflows, risk data, prospectus documents and SEC filings, sourced from SEC filings.
- Type: US mutual fund
- Manager: Mfs Series Trust XII
- Category: Long Total / Aggregate Bond
- Assets under management: $33.80M
- 1-year return: 4.3%
- Ticker: MCBMX
- SEC CIK: 0001330967
- SEC series ID: S000076470
- Share class ID: C000236387
MCBMX Holdings
Top 10 holdings of MFS Core Bond Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| MFS Institutional Money Market Portfolio | 4.81% |
| United States of America | 4.32% |
| United States of America | 2.75% |
| United States of America | 2.70% |
| United States of America | 1.77% |
| United States of America | 1.64% |
| United States of America | 1.58% |
| United States of America | 1.36% |
| United States of America | 1.33% |
| NTT Finance Corp. | 1.20% |
MCBMX Portfolio Allocation
Asset-class allocation of MFS Core Bond Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Fixed Income | 56.1% |
| Securitized | 43.2% |
| Cash & Equivalents | 4.8% |
MCBMX Performance
Total returns for MCBMX (as of 2026-08-01), from SEC filings.
| Period | Total return |
|---|---|
| YTD | 0.2% |
| 1 year | 4.3% |
| 3 years (annualised) | 3.9% |
MCBMX Risk Information
Risk metrics for MCBMX, derived from monthly returns in SEC filings.
- 1-year volatility (annualised): 3.4%
MCBMX Costs and Fees
MCBMX costs about $33 per $10,000 invested per year in fund expenses.
- Net expense ratio: 0.33%
- Gross expense ratio: 1.23%
- Portfolio turnover: 139%
- Brokerage commissions: 0.28 bps of average net assets (SEC N-CEN)
MCBMX Cashflows
Over the 12 months to 2026-04, MFS Core Bond Fund had net inflows of $2.00M, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-04 | $119.98K |
| 2026-03 | $109.68K |
| 2026-02 | $104.50K |
| 2026-01 | −$143.22K |
| 2025-12 | $191.82K |
| 2025-11 | $257.57K |
MCBMX Debt Constituents
Largest debt holdings of MFS Core Bond Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Debt holding | % of net assets |
|---|---|
| United States of America | 4.32% |
| United States of America | 2.75% |
| United States of America | 2.70% |
| United States of America | 1.77% |
| United States of America | 1.64% |
| United States of America | 1.58% |
| United States of America | 1.36% |
| United States of America | 1.33% |
| NTT Finance Corp. | 1.20% |
| United States of America | 1.12% |
MCBMX Prospectus and SEC Filings
Official MFS Core Bond Fund filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.
Related Funds
Other Long Total / Aggregate Bond funds tracked on ABC INVEST:
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, annual data from Form N-CEN, and shareholder reports from Form N-CSR.