Investment Objective

Seeks high level of income and opportunity for capital appreciation consistent with preservation of capital.

Fees and Expenses of the Portfolio

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Portfolio. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and example below. The table does not reflect fees or expenses that may be charged in connection with variable annuities and variable life insurance policies issued by the insurance companies which offer the Portfolio as an underlying investment option. If such charges were included, the following fees and expenses would be higher.

Shareholder Fees (fees paid directly from your investment): —

Example. This Example is intended to help you compare the cost of investing your variable contract assets in the Portfolio with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Portfolio for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. The costs indicated below do not reflect the additional expenses of variable contracts. These costs would be higher if variable contract charges were added. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Portfolio Turnover. The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 21% of the average value of its portfolio.

Principal Investment Strategies

The Portfolio invests primarily in intermediate-term and long-term fixed-income securities. These generally have a remaining maturity of 5 years or more when purchased. Under normal circumstances, at least 80% of the Portfolio’s net assets (plus borrowings for investment purposes, if any) will be invested in:

This Portfolio normally includes debt securities with varying maturities selected from various industries, depending upon the Adviser’s evaluation of current and anticipated market conditions. This Portfolio may also invest in U.S. government securities as well as the debt securities of foreign issuers.

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The portfolio managers consider a variety of factors in determining whether to sell a security, including changes in market conditions, changes in prospects for the security, alternative investment possibilities and other factors they believe to be relevant.

Principal Risks

There is no assurance that the Portfolio will meet its investment objective. The value of your investment in the Portfolio and the amount of the return you receive on your investment may fluctuate significantly. You could lose money, or have less return than the market in general, by investing in the Portfolio. The principal risks of investing in the Portfolio are:

Market Risk — A security’s price may change in response to changes in conditions in securities markets in general. Markets tend to move in cycles with periods of rising prices and periods of falling prices. They can decline for many reasons, including adverse political or economic developments domestically or abroad, changes in investor psychology, or heavy institutional selling. In the case of debt securities, changes in the overall level of interest rates affect the security’s price. A significant national or international event, natural disaster or widespread health crisis, such as the COVID-19 global pandemic, could cause substantial market volatility, exchange trading suspensions and closures, severe market dislocations and liquidity constraints, impact the ability to complete redemptions, and affect the Portfolio’s performance.

Liquidity Risk — The Portfolio may not be able to sell some or all of its securities at desired prices or may be unable to sell the securities at all, particularly during times of market turmoil. Markets may become illiquid when, for instance, there are few, if any, interested buyers or sellers or when dealers are unwilling or unable to make a market for certain securities. The Portfolio may not be able to sell a restricted or illiquid security at a favorable time or price, thereby decreasing the Portfolio’s overall liquidity. Further, the lack of an established secondary market may make it more difficult to value illiquid securities. If the Portfolio is forced to sell an illiquid security to meet redemption requests or for other cash needs, the Portfolio may be forced to sell at a loss.

Interest Rate Risk — Prices of fixed-income securities rise and fall in response to changes in the interest rates paid by similar securities. Generally, when interest rates rise, prices of fixed-income securities fall. However, market factors, such as the demand for particular fixed-income securities, may cause the price of certain fixed-income securities to fall while the prices of other securities rise or remain unchanged. Interest rate changes have a greater effect on the price of fixed-income securities with longer maturities. A wide variety of market factors can affect interest rates. Recent and potential future changes in monetary policy made by central banks and/or their governments are likely to affect the level of interest rates. The Portfolio may be subject to heightened interest rate risk due to certain changes in monetary policy. Rising interest rates may expose fixed-income markets to increased volatility and may reduce the liquidity of certain Portfolio investments. These developments also could cause more fluctuation in the Portfolio’s net asset value or make it more difficult for the Portfolio to accurately value its securities. These developments or others could also cause the Portfolio to face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio as well as the value of your investment. The amount of assets deemed illiquid remaining within the Portfolio may also increase, making it more difficult to meet shareholder redemptions and further adversely affecting the value of the Portfolio.

LIBOR Risk — Instruments in which the Portfolio invests may pay interest based on the London Interbank Offered Rate (“LIBOR”). The phase out of the three-, six- and twelve-month U.S. dollar LIBOR settings has been delayed until mid-2023, but all other LIBOR settings, including the one-week and two-month U.S. dollar LIBOR settings have already been phased out. The Federal Reserve has designated the Secured Overnight Financing Rate (“SOFR”) as the replacement rate in certain financial instruments after June 23, 2023. The nature of the impact of the transition away from LIBOR on the Portfolio, issuers of instruments in which the Portfolio invests, and financial markets generally is unknown.

Credit Risk — The Portfolio may lose money if the issuer or guarantor of a fixed income security is unable or unwilling to make scheduled interest or principal payments, which may reduce the Portfolio’s income and market value.

Issuer Risk — The value of a security may decline for reasons related to the issuer, such as earnings stability, overall financial soundness, management performance and reduced demand for the issuer’s goods or services.

Call or Prepayment Risk — During periods of falling interest rates, a bond issuer may “call” or repay its high-yielding bond before the bond’s maturity date. If forced to invest the unanticipated proceeds at lower interest rates, the Portfolio would experience a decline in income. The ability of an issuer of a debt security to repay principal prior to a security’s maturity can cause greater price volatility if interest rates change.

Government Securities Risk — Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. government. Some obligations are backed only by the credit of the issuing agency or instrumentality, and, in some cases, there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security the Portfolio holds does not apply to the market value of the security or to shares of the Portfolio. A security backed by the U.S. Treasury or the full faith and credit of the U.S. government is guaranteed only as to the timely payment of interest and

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principal when held to maturity. The risks associated with an investment in Credit Risk Transfer securities (“CRTs”) differ from the risks associated with an investment in mortgage-backed securities issued by Government Sponsored Enterprises (“GSEs”) because, in CRTs, some or all of the credit risk associated with the underlying mortgage loans is transferred to the end-investor.

Sovereign Debt Risk — Sovereign debt securities are issued or guaranteed by foreign governmental entities. These investments are subject to the risk that a governmental entity may delay or refuse to pay interest or repay principal on its sovereign debt. There is no legal process for collecting sovereign debts that a government does not pay.

Foreign Investments Risk — Foreign investments involve risks not normally encountered with domestic securities. These include political, regulatory and economic instability in some countries, the imposition of economic sanctions, changes in currency rates and market inefficiencies. The laws of some foreign countries may limit the Portfolio’s ability to invest in securities of certain issuers organized under the laws of those countries. Trade tensions and economic sanctions on individuals and companies can contribute to market volatility. This may adversely impact the Portfolio’s performance.

Performance

The accompanying bar chart and table provide some indication of the risks of investing in the Portfolio. They show changes in the Portfolio’s performance for each of the last ten years and the Portfolio’s average annual returns for the last one year, five years and ten years compared to those of a broad-based securities market index. The Portfolio’s past performance does not necessarily indicate how it will perform in the future. Variable contract charges are not reflected in the chart or table. If they were, the returns would be less than those shown.

During the period shown in the bar chart, the Portfolio’s highest return for a quarter was 10.52%. That was the quarter ended on June 30, 2020. The lowest return for a quarter was -7.44%. That was the quarter ended on March 31, 2022. To obtain performance information up to the most recent month end, call toll free 877.781.6392.

Management

Ohio National Investments, Inc. serves as the investment adviser for the Portfolio. Gary Rodmaker, CFA, FLMI, Senior Vice President, Fixed Income Securities and Chief Investment Officer for ONLIC, has been a portfolio manager for the Portfolio since January 2015.

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Purchase and Sale of Fund Shares

Shares of the Portfolio are offered only to separate accounts of insurance companies, which use the Portfolio shares as an underlying investment for variable annuities and variable life insurance contracts, and to portfolios of the Fund in connection with ONLIC, ONLAC and National Security’s variable annuity contracts and variable life insurance policies. You may select funds and make transfers among fund options as described in your variable contract prospectus. The separate accounts of the insurance companies may purchase and redeem Portfolio shares, at their net asset value next computed, each day the New York Stock Exchange is open for unrestricted trading. Please read your variable contract prospectus for more information about your variable contract.

Tax Information

The tax treatment of payments made from a variable contract is described in the contract’s prospectus. Generally, contract owners are not taxed on income or gains realized within their contract until they receive payments from the contract.

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