2023

Semiannual Report

All Data as of June 30, 2023

Guardian Core Fixed Income VIP Fund

Guardian Core Fixed Income VIP Fund

By investing in the Fund, you incur two types of costs: (1) transaction costs and (2) ongoing costs, including, as applicable, investment advisory fees, distribution and/or service (12b-1) fees, if any, and other Fund expenses. The example below is intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds.

The example is based on an investment of $1,000 invested at the beginning of the period and held for the entire period from January 1, 2023 to June 30, 2023. The table below shows the Fund’s expenses in two ways:

Expenses based on actual return

This section of the table provides information about actual account values and actual expenses. You may use the information in this section, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000 (for example, an $8,600 account value divided by $1,000 = 8.6), then multiply the result by the number in the section under the heading entitled “Expenses Paid During Period” to estimate the expenses you paid on your account during this period.

Expenses based on hypothetical 5% return for comparison purposes

This section of the table provides information about hypothetical account values and hypothetical expenses based on the Fund’s actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund’s actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the Fund with the cost of investing in other mutual funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds.

Note that the expenses shown in the table are meant to highlight your ongoing costs only and do not reflect any transactional costs, such as sales charges (loads), redemption fees, or exchange fees. Therefore the second section is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds. If these transactional costs were included, your costs would have been higher. Charges and expenses at the insurance company separate account level are not reflected in the table.

June 30, 2023 (unaudited)

1. Organization

Guardian Variable Products Trust (the “Trust”), a Delaware statutory trust organized on January 12, 2016, is registered under the Investment Company Act of 1940, as amended (the “1940 Act”), as an open-end management investment company. The Trust currently has twenty-four series. Guardian Core Fixed Income VIP Fund (the “Fund”) is a series of the Trust. The Fund is a diversified fund and commenced operations on May 2, 2022. The financial statements for other series of the Trust are presented in separate reports.

The Trust has authorized an unlimited number of shares of beneficial interest with no par value. Shares are bought and sold at closing net asset value (“NAV”). Shares of the Fund are only sold to certain separate accounts of The Guardian Insurance & Annuity Company, Inc. (“GIAC”) that fund certain variable annuity contracts and variable life insurance policies issued by GIAC. GIAC is a wholly-owned subsidiary of The Guardian Life Insurance Company of America (“Guardian Life”).

The Fund seeks to provide a high level of current income and capital appreciation without undue risk to principal.

2. Significant Accounting Policies

The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements. The Fund follows the investment company accounting and reporting guidance of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification Topic 946 Financial Services – Investment Companies. The following policies are in conformity with accounting principles generally accepted in the United States of America (“GAAP”). The preparation of financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in the financial statements. Actual results could differ from those estimates.

a. Investment Valuations The Board of Trustees has designated Park Avenue Institutional Advisers LLC (“Park Avenue”) as the valuation designee for the Fund pursuant to Rule 2a-5 under the 1940 Act. Park Avenue has established a Fair Valuation Committee and has adopted fair valuation procedures that provide methodologies for fair valuing securities. These procedures include monitoring the appropriateness of fair values based on results of ongoing valuation oversight, including but not limited to consideration of

security specific events, market events, and pricing vendor and broker-dealer due diligence. The Fair Valuation Committee oversees and carries out the policies for the valuation of investments held in the Fund. The Fair Valuation Committee is responsible for discussing and assessing the potential impacts to the fair values on an ongoing basis, and reports to the Board of Trustees on at least a quarterly basis.

The valuations of debt securities for which quoted bid prices are readily available are valued at the bid price by independent pricing services (each, a “Service”). Debt securities for which quoted bid prices are not readily available are valued by a Service at the evaluated bid price provided by the Service or the bid price provided by an independent broker-dealer or at a calculated price based on the spread to an appropriate benchmark provided by such broker-dealer.

Equity securities traded on an exchange other than NASDAQ Stock Market, LLC (“NASDAQ”) are valued at the last reported sale price on the principal exchange or market on which they are traded; or, if there were no sales that day, at the mean between the closing bid and ask prices. Securities traded on the NASDAQ are generally valued at the NASDAQ official closing price, which may not be the last sale price. If the NASDAQ official closing price is not available for a security, that security is generally valued at the mean between the closing bid and ask prices. Repurchase agreements are carried at cost, which approximates fair value (see Note 5c). Foreign securities are valued in the currencies of the markets in which they trade and then converted to U.S. dollars by the application of foreign exchange rates at the close of the New York Stock Exchange (“NYSE”).

Exchange-traded financial futures contracts are valued at the last settlement price on the market where they are primarily traded.

Securities for which market quotations are not readily available or securities whose values have been materially affected by events occurring before the Fund’s valuation time but after the close of the securities’ principal exchange or market are valued at their fair values as determined in good faith by Park Avenue, as the Board of Trustee’s valuation designee (as defined in Rule 2a-5 under the 1940 Act), in accordance with Park Avenue’s procedures and under the general oversight of the Board of Trustees. Valuations reflected in this report are as of the report date. As a result, changes in valuation due to market events and/or issuer related events after the report date and prior to issuance of the report are not reflected herein.

Various inputs are used in determining the valuation of the Fund’s investments. These inputs are summarized in three broad levels listed below.

Inputs may include price information, volatility statistics, specific and broad credit data, liquidity statistics, and other factors. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input; both individually and in aggregate, that is significant to the fair value measurement. However, the determination of what constitutes “observable” requires significant judgment by the Trust. The Trust considers observable data to be that market data which is readily available, regularly distributed or updated, reliable and verifiable, and provided by independent sources that are actively involved in the relevant market. The inputs or methodology used for valuing securities are not necessarily an indication of the risk associated with investing in those securities. Changes in valuation techniques may result in transfers into or out of a financial instrument’s assigned level within the hierarchy.

The FASB requires reporting entities to make disclosures about purchases, sales, issuances and settlements of Level 3 securities on a gross basis. For the six months ended June 30, 2023, there were no transfers into or out of Level 3 of the fair value hierarchy.

In determining a financial instrument’s placement within the hierarchy, the Trust separates the Fund’s investment portfolio into two categories: investments and derivatives (e.g., futures). A summary of inputs used to value the Fund’s assets and liabilities carried at fair value as of June 30, 2023 is included in the Schedule of Investments.

Investments Investments whose values are based on quoted market prices in active markets, and are therefore classified within Level 1, include active listed equities. Investments that trade in markets that are not considered to be active, but are valued based on quoted

market prices, dealer quotations or alternative pricing sources supported by observable inputs are classified within Level 2. These include certain U.S. government and sovereign obligations, most government agency securities, investment-grade corporate bonds, certain mortgage products, state, municipal and provincial obligations, and certain foreign equity securities, including securities whose prices may have been affected by events occurring after the close of trading on their principal exchange or market and, as a result, whose values are determined by a pricing service as described above, or securities whose values are otherwise determined using fair valuation methods approved by the Fund’s Board of Trustees.

Investments classified within Level 3 have significant unobservable inputs, as they trade infrequently or not at all. Level 3 investments include, among others, private placement securities. When observable prices are not available for these securities, the Trust uses one or more valuation techniques for which sufficient and reliable data is available. The inputs used by the Trust in estimating the value of Level 3 investments include, for example, the original transaction price, recent transactions in the same or similar instruments, completed or pending third-party transactions in the underlying investment or comparable issuers, subsequent rounds of financing, recapitalizations, and other transactions across the capital structure. Level 3 investments may also be adjusted to reflect illiquidity and/or non-transferability, with the amount of such discount estimated by the Trust in the absence of market information. Assumptions used by the Trust due to the lack of observable inputs may significantly impact the resulting fair value and therefore the Fund’s results of operations. As of June 30, 2023, the Fund had no securities classified as Level 3.

Derivatives Exchange-traded derivatives, such as futures contracts, exchange-traded option contracts and certain swaps, are typically classified within Level 1 or Level 2 of the fair value hierarchy depending on whether or not they are deemed to be actively traded. Certain non-exchange-traded derivatives, such as generic forwards, certain swaps and options, have inputs which can generally be corroborated by market data and are therefore classified within Level 2.

b. Securities Transactions Securities transactions are accounted for on the date securities are purchased or sold (trade date). Realized gains or losses on securities transactions are determined on the basis of specific identification.

c. Futures Contracts The Fund may enter into financial futures contracts. In entering into such contracts, the Fund is required to deposit with the counterparty, either in cash or securities, an amount equal to a certain percentage of the face value of the contract. Subsequent payments are received or made by the Fund each day, depending on the daily fluctuations in the values of the contracts, and are recorded for financial statement purposes as variation margin received or paid by the Fund. Daily changes in variation margin are recognized as unrealized gains or losses by the Fund. The Fund may not achieve the anticipated benefits of the financial futures contracts and may realize a loss.

d. Credit Derivatives The Fund may enter into credit derivatives, including credit default swaps on individual obligations or credit indices. The Fund may use these investments (i) as alternatives to direct long or short investment in a particular security or securities, (ii) to adjust the Fund’s asset allocation or risk exposure, (iii) to enhance potential return, or (iv) for hedging purposes. The use by the Fund of credit default swaps may have the effect of creating a short position in a security. Credit derivatives can create investment leverage and may create additional investment risks that may subject the Fund to greater volatility than investments in more traditional securities, as described in the Statement of Additional Information.

The Fund may enter into credit default swap agreements either as a buyer or seller. The Fund may buy protection under a credit default swap to attempt to mitigate the risk of default or credit quality deterioration in one or more individual holdings or in a segment of the fixed income securities market. The Fund may sell protection under a credit default swap in an attempt to gain exposure to an underlying issuer’s credit quality characteristics without investing directly in that issuer.

For swaps entered with an individual counterparty, the Fund bears the risk of loss of the uncollateralized amount expected to be received under a credit default swap agreement in the event of the default or bankruptcy of the counterparty. Credit default swap agreements are generally valued at a price at which the counterparty to such agreement would terminate the agreement. The Fund may also enter into cleared swaps.

In entering into swap contracts, the Fund is required to deposit with the broker (or for the benefit of the broker), either in cash or securities, an amount equal to a percentage of the notional value of the contract. Subsequent payments are received or made by the Fund each day, depending on the daily fluctuations in the values of the contracts, and are recorded for financial

statement purposes as variation margin received or paid by the Fund. Daily changes in variation margin are recognized as unrealized gains or losses by the Fund. The Fund may not achieve the anticipated benefits of the swap contracts and may realize a loss. During the six months ended June 30, 2023, the Fund entered into credit default swaps for risk exposure management and to enhance potential return.

e. Options Transactions The Fund can write (sell) put and call options on securities and indexes to earn premiums, for hedging purposes, for risk management purposes or otherwise as part of its investment strategies. In writing options, the Fund is required to deposit with the broker or counterparty, either in cash or securities, an amount equal to a percentage of the face value of the options. When an option is written, the premium received is recorded as an asset with an equal liability that is subsequently marked to market to reflect the market value of the written option. These liabilities, if any, are reflected as written options, at value, in the Fund’s Statement of Assets and Liabilities. Premiums received from writing options which expire unexercised are recorded on the expiration date as a realized gain. The difference between the premium received and the amount paid on effecting a closing purchase transaction, including brokerage commissions, is also treated as a realized gain, or if the premium is less than the amount paid for the closing purchased transactions, as a realized loss. If a written call option is exercised, the premium is added to the proceeds from the sale of the underlying security in determining whether there has been a realized gain or loss. If a written put option is exercised, the premium reduces the cost basis of the security. In writing an option, the Fund bears the market risk of an unfavorable change in the price of the security underlying the written option. Exercise of a written option could result in the Fund purchasing or selling a security at a price different from its current market value. There were no options transactions as of June 30, 2023.

f. Investment Income Dividend income net of foreign taxes withheld, if any, is generally recorded on the ex-dividend date. Distributions received from real estate investment trusts, if any, may be classified as dividends, capital gains and/or return of capital. Interest income, which includes amortization/accretion of premium/discount, is determined using the interest income accrual method, and is accrued and recorded daily.

g. Allocation of Income and Expenses Many of the expenses of the Trust can be directly attributed to a specific series of the Trust. Expenses that cannot be

directly attributed to a specific series of the Trust are generally apportioned among all the series in the Trust, based on relative net assets. In calculating net asset value per share for each series of the Trust, investment income, realized and unrealized gains and losses, and expenses other than series-specific expenses are allocated daily to each series based upon the proportion of net assets attributable to each series.

3. Transactions with Affiliates

a. Investment Advisory Fee and Expense Limitation Under the terms of the advisory agreement, which, after its two year initial term, is reviewed and approved annually by the Board of Trustees, the Fund pays an investment advisory fee to Park Avenue. Park Avenue is a wholly-owned subsidiary of Guardian Life and receives an investment advisory fee at an annual rate of 0.45% of the first $300 million, and 0.40% in excess of $300 million of the Fund’s average daily net assets. The fee is accrued daily and paid monthly. The Fund has no sub-adviser.

Park Avenue has contractually agreed through April 30, 2024 to waive certain fees and/or reimburse certain expenses incurred by the Fund to the extent necessary to limit the Fund’s total annual operating expenses after fee waiver and/or expense reimbursement to 0.50% of the Fund’s average daily net assets (excluding, if applicable, any acquired fund fees and expenses, taxes, interest, transaction costs and brokerage commissions, litigation and extraordinary expenses). The limitation may not be increased or terminated prior to this time without action by the Board of Trustees and may be terminated only upon approval of the Board of Trustees. Amounts waived or reimbursed by Park Avenue pursuant to any expense limitation will not be subject to Park Avenue’s recoupment rights. For the six months ended June 30, 2023, Park Avenue waived fees and/or paid Fund expenses in the amount of $53,125.

b. Compensation of Trustees and Officers Trustees and officers who are interested persons of the Trust, as defined in the 1940 Act, receive no compensation from the Fund, except for the Chief Compliance Officer of the Trust. Trustees of the Trust who are not interested persons of the Trust, and the Chief Compliance Officer, receive compensation and reimbursement of expenses from the Trust.

4. Federal Income Taxes

a. Distributions to Shareholders For federal income tax purposes, the Fund is treated as a disregarded entity (“DRE”). As a DRE, the Fund is not subject to an entity-level income tax; and any income, gains, losses,

deductions, taxes, and credits of the Fund would instead be “passed through” directly to the separate accounts of GIAC that invest in the Fund and retain the same character for U.S. federal income tax purposes. In addition, the Fund is not required to distribute taxable income and capital gains for U.S. federal income tax purposes. Therefore, no dividends and capital gains distributions were paid by the Fund.

5. Investments

a. Investment Purchases and Sales The cost of investments and U.S. government agency obligations purchased and the proceeds from U.S. government agency obligations and other investments sold (excluding short-term investments and to be announced (TBA) securities) for the six months ended June 30, 2023, were as follows: