Short-Term Bond Portfolio
Data updated: 2026-08-20
C000050281 — Short-Term Bond Portfolio. Intermediate Total / Aggregate Bond · $400.75M AUM · 0.40% expense ratio. Holdings, fees, performance and SEC filings.
C000050281 Fund Overview
Short-Term Bond Portfolio is a US mutual fund managed by Northwestern Mutual Series Fund INC, categorised as Intermediate 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: Northwestern Mutual Series Fund INC
- Category: Intermediate Total / Aggregate Bond
- Assets under management: $400.75M
- 1-year return: 3.6%
- SEC CIK: 0000742212
- SEC series ID: S000018233
- Share class ID: C000050281
C000050281 Investment Objective and Strategy
Short-Term Bond Portfolio describes its objective and strategy as follows, from its latest prospectus filed with the SEC by Northwestern Mutual Series Fund INC.
Investment objective
The investment objective of the Portfolio is to provide as high a level of current income as is consistent with prudent investment risk.
Principal investment strategy
Normally, the Portfolio invests at least 80% of net assets (plus any borrowings for investment purposes) in debt securities. The adviser normally selects investment grade securities which are generally securities rated investment grade by major credit rating agencies (BBB- or higher by S&P; Baa3 or higher by Moodys; BBB- or higher by Fitch) or, if unrated, determined by the Portfolios adviser to be of comparable quality. Also, the Portfolio may invest up to 20% of net assets in foreign securities, including those of issuers located in emerging markets, consistent with its investment objective. Foreign securities held by the Portfolio may consist of both U.S. dollar and non-U.S. dollar denominated securities. Debt securities may be of any maturity, but under normal market conditions, the Portfolios effective dollar-weighted average maturity will not exceed three years.
The Portfolio primarily invests in corporate, government and mortgage- and asset-backed securities. The Portfolios mortgage-related securities investments may include collateralized mortgage obligations as well as commercial and residential mortgage-backed securities. The Portfolios investments in asset-backed securities include asset-backed auto loans. The Portfolio may use a variety of derivatives, such as futures, options, forwards, and swaps for a number of purposes, such as for exposure or hedging. The Portfolio specifically uses interest rate futures and credit default index swap indexes (CDX). Interest rate futures are typically used in an effort to manage its exposure to changes in interest rates or to adjust portfolio duration. Credit default swaps are typically used in an effort to protect the value of certain portfolio holdings or to manage the Portfolios overall exposure to changes in credit quality.
A CDX is a swap on an index of credit default swaps. CDXs allow an investor to manage credit risk or take a position on a basket of credit entities (such as credit default swaps or a reference index) rather than transacting in a single-name credit default swap. Additionally, the Portfolio uses mortgage-backed securities on a delayed delivery or forward commitment basis through the to-be-announced (TBA) market as a means of adjusting the Portfolios duration and gaining exposure to investment-grade bonds. The adviser uses both a top down and bottom up investment approach to construct the portfolio of investments. The top down investment approach involves an evaluation by the adviser of the overall macroeconomic environment and its potential impact on the level and direction of interest rates.
The adviser then identifies sectors it believes have the best potential for performance based on its economic outlook. The bottom up investment approach focuses on fundamental research of individual issuers. Investment decisions reflect the advisers outlook for interest rates and the economy, as well as the prices, yields, and credit quality of various securities in which the Portfolio may invest . The adviser may engage in active and frequent trading of portfolio securities to achieve its investment objective. The adviser may sell a portfolio security for a variety of reasons, such as to adjust the Portfolios average maturity, duration, or overall credit quality or to shift assets into and out of higher-yielding or lower-yielding securities or certain sectors.
C000050281 Holdings
Top 10 holdings of Short-Term Bond Portfolio by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| United States Treasury | 8.26% |
| United States Treasury | 6.35% |
| United States Treasury | 5.32% |
| United States Treasury | 1.41% |
| Medline Borrower LP | 0.51% |
| Freddie Mac | 0.50% |
| Heineken NV | 0.48% |
| Fannie Mae | 0.47% |
| Videotron Ltd | 0.42% |
| Fannie Mae | 0.39% |
C000050281 Portfolio Allocation
Asset-class allocation of Short-Term Bond Portfolio by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Fixed Income | 61.3% |
| Securitized | 34.5% |
| Cash & Equivalents | 1.8% |
C000050281 Performance
Total returns for C000050281 (as of 2026-10-01), from SEC filings.
| Period | Total return |
|---|---|
| YTD | 1.0% |
| 1 year | 3.6% |
| 3 years (annualised) | 5.2% |
| 5 years (annualised) | 2.3% |
C000050281 Risk Information
Risk metrics for C000050281, derived from monthly returns in SEC filings.
- 1-year volatility (annualised): 1.1%
C000050281 Costs and Fees
C000050281 costs about $40 per $10,000 invested per year in fund expenses.
- Net expense ratio: 0.40%
- Gross expense ratio: 0.40%
- Portfolio turnover: 113%
- Brokerage commissions: 0.21 bps of average net assets (SEC N-CEN)
C000050281 Cashflows
Over the 12 months to 2026-06, Short-Term Bond Portfolio had net inflows of $11.70M, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-06 | −$1.14M |
| 2026-05 | $2.16M |
| 2026-04 | −$3.55M |
| 2026-03 | −$1.06M |
| 2026-02 | −$979.62K |
| 2026-01 | −$960.22K |
C000050281 Debt Constituents
Largest debt holdings of Short-Term Bond Portfolio by percentage of net assets, from the latest SEC N-PORT filing.
| Debt holding | % of net assets |
|---|---|
| United States Treasury | 8.26% |
| United States Treasury | 6.35% |
| United States Treasury | 5.32% |
| United States Treasury | 1.41% |
| Medline Borrower LP | 0.51% |
| Heineken NV | 0.48% |
| Wells Fargo & Company | 0.39% |
| Salesforce, Inc. | 0.35% |
| Gartner, Inc. | 0.32% |
| Bayer US Finance Ii LLC | 0.30% |
C000050281 Prospectus and SEC Filings
Official Short-Term Bond Portfolio filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.
- Prospectus (485BPOS) — filed 2026-04-24
- Prospectus (485BPOS) — filed 2025-04-25
- Prospectus supplement (497) — filed 2024-04-30
- Portfolio holdings (N-PORT) — filed 2026-08-20
- Portfolio holdings (N-PORT) — filed 2026-05-27
- Portfolio holdings (N-PORT) — filed 2026-02-23
- Annual census (N-CEN) — filed 2026-03-12
- Annual census (N-CEN) — filed 2025-03-11
Related Funds
Other Intermediate 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.