High Yield Bond Portfolio
NORTHWESTERN MUTUAL SERIES FUND INC
Expense ratio
Net assets1
$698.24M
Holdings1
520
Category
Taxable Bond
Return

Investment objective & strategy

As of May 2, 2025 · prospectus

Objective. The investment objective of the Portfolio is to achieve high current income and capital appreciation.

Strategy. Normally, the Portfolio invests at least 80% of net assets (plus any borrowings for investment purposes) in non-investment grade debt securities. Non-investment grade securities are generally securities rated below investment grade by major credit rating agencies (BB+ or lower by S&P; Ba1 or lower by Moodys; BB+ or lower by Fitch), or, if unrated, determined by the Portfolios adviser to be of comparable quality. There is no minimal acceptable rating for a security to be purchased or held by the Portfolio. The Portfolio may invest up to 30% of net assets in non-investment grade foreign securities, including those of issuers located in emerging markets, consistent with its investment objective. Foreign securities held by the Portfolio consist primarily of U.S. dollar … Normally, the Portfolio invests at least 80% of net assets (plus any borrowings for investment purposes) in non-investment grade debt securities. Non-investment grade securities are generally securities rated below investment grade by major credit rating agencies (BB+ or lower by S&P; Ba1 or lower by Moodys; BB+ or lower by Fitch), or, if unrated, determined by the Portfolios adviser to be of comparable quality. There is no minimal acceptable rating for a security to be purchased or held by the Portfolio. The Portfolio may invest up to 30% of net assets in non-investment grade foreign securities, including those of issuers located in emerging markets, consistent with its investment objective. Foreign securities held by the Portfolio consist primarily of U.S. dollar denominated securities but may also include non-U.S. dollar denominated securities. The securities in which the Portfolio primarily invests are considered speculative and are sometimes known as junk bonds. These securities tend to offer higher yields than higher rated securities of comparable maturities primarily because of the markets greater uncertainty about the issuers ability to make all required interest and principal payments, and therefore about the returns that will in fact be realized by the Portfolio. The adviser selects securities that it believes have attractive investment characteristics and seeks to minimize default risk and other risks through careful security selection and diversification. The advisers securities selection process consists of a credit-intensive, fundamental analysis of the issuer. The advisers analysis focuses on the issuers financial condition, business and product strength, competitive position and management expertise. Further, the adviser considers current economic, financial market and industry factors, which may affect the issuer. The adviser does not limit the Portfolios investments to securities of a particular maturity range and does not target an average effective maturity or duration. In addition, as part of its security selection process, among other factors, the adviser also evaluates whether environmental, social and governance factors could have positive or negative impact on the risk profiles of many issuers in the universe of securities in which the Portfolio may invest. Examples of ESG factors that may be considered include, but are not limited to, carbon emissions, waste and harmful substance management, product and employee safety, human capital management and labor relations, and corporate governance structure and oversight. Specific factors and the weight given to those factors will vary relative to the material impact it may have on the risk assessment of the issuer. The adviser may also consider information derived from active engagement conducted by its in-house stewardship team with certain issuers or guarantors. This qualitative analysis does not automatically result in including or excluding specific securities but may be used by the adviser as an additional input to Portfolio risk/return characteristics. Consideration of ESG factors may not be determinative in the advisers investment process and the adviser may conclude that other attributes of an investment outweigh ESG considerations when making investment decisions for the Portfolio. The adviser strives to adhere to a strong sell discipline and generally effects a sale if it believes a securitys future total return has become less attractive relative to other securities, the company begins to perform poorly, the industry outlook changes, or any other event occurs that changes the advisers conclusion.

Top holdings

As of March 31, 2026 · N-PORT
SecurityTickerValue% of fund
ARDONAGH GRP. FIN. 8.875% ARDGRP $7.15M 1.02%
Medline Borrower, L.P. $5.95M 0.85%
McAfee Corp $5.64M 0.81%
TIHLLC 7 1/8 06/01/31 TIHLLC $5.12M 0.73%
MADISON IAQ LLC SR UNSECURED 144A 06/29 5.875 MADIAQ $5.03M 0.72%
TEP 6.75 03/15/34 144A TEP $4.95M 0.71%
SKX 10 07/15/33 144a SKX $4.89M 0.70%
ULTI 6.875 02/01/31 144A ULTI $4.89M 0.70%
USI INC/NY SR UNSECURED 144A 01/32 7.5 COMINV $4.76M 0.68%
HUB INTL. LTD 7.375% HBGCN $4.72M 0.68%
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Allocation by sector

As of March 31, 2026 · N-PORT
View portfolio breakdown →

Portfolio moves

Dec 31, 2025 → Mar 31, 2026
Opened
36
Exited
37
Increased
38
Decreased
23
Unchanged
423

How many positions this fund opened, exited, grew, trimmed, or left unchanged between its two most recent N-PORT snapshots — net changes between point-in-time reports, not a trade log.

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Similar funds

Funds whose portfolios most overlap this one, by weight
FundOverlapNet exp.
Federated Hermes Institutional High Yield Bond Fund · FIHBX, FIHLX, FIHAX, FIHCX 80% 0.49%
High Yield Bond Core Fund 77%
Federated Hermes Opportunistic High Yield Bond Fund · FHYTX, FHTIX, FHYAX, FHYCX, FHYLX 71% 0.72%
View all similar funds →

Advisers

As of December 31, 2025 · N-CEN
FirmRole
Federated Investment Management Company Sub-adviser
Mason Street Advisors, LLC Adviser

Footnotes

  1. Net assets and holdings count as of March 31, 2026, from the fund's N-PORT filing.

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