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HARBOR ETF TRUST

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Harbor Multi-Asset Explorer ETFFund Summary

Objective, Primary [Text Block]

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The Fund seeks to provide long-term total return while limiting downside risk.

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. 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.

Portfolio Turnover [Heading]

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Portfolio Turnover

Other Expenses, New Fund, Based on Estimates [Text]

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“Other Expenses” and “Acquired Fund Fees and Expenses” are estimated for the current fiscal year.

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other exchange-traded funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, under these assumptions, your costs would be:

Strategy Narrative [Text Block]

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To seek to achieve the Fund’s investment objective, Harbor Capital Advisors Inc., the Fund’s investment adviser (the “Advisor”), allocates the Fund’s assets among various asset classes and market sectors based on its assessment of global economic and market conditions, primarily through investments in a diversified portfolio of exchange-traded funds, including other funds managed by the Advisor (“Underlying Funds”).The Fund invests in Underlying Funds that provide exposure to one or more broad asset classes, such as equities, fixed income securities of any credit quality (including below-investment grade bonds, also known as high-yield bonds or “junk” bonds), real estate investment trusts, commodities, and cash and cash equivalents. The Fund invests, through Underlying Funds, in markets around the world, including both in developed and emerging markets. The Fund generally invests in Underlying Funds that seek to track indices, including those designed to provide exposure to particular sectors or industries (such as communication services, financials and/or technology) or style factors (such as growth, value, and/or low volatility). However, the Fund may invest in Underlying Funds that are actively managed. While the Fund generally invests through Underlying Funds, it may also invest directly in equity and fixed income securities and derivatives, such as futures and options, in limited circumstances where the Advisor believes that a particular exposure is better achieved through direct investments.The Advisor’s broad-based approach to managing the Fund combines both systematic and discretionary research and analysis. In managing the Fund, the Advisor seeks to understand the economic and business cycle, and the risks and opportunities the current cycle presents using its proprietary multi-factor model that includes growth, liquidity, and inflation factors (the “model”). The model categorizes the business cycle into various regimes based primarily on the intersection of these three macro factors – growth, liquidity, and inflation – using a probabilistic approach to assess the future state of these factors. The Fund employs an asset allocation strategy driven by regime modeling, which seeks to capture upside during risk-friendly business cycle regimes and preserve capital in risk-averse regimes. The Fund utilizes a four-step process that involves: (1) regime identification; (2) return estimation;(3) portfolio construction; and (4) qualitative review.Step 1 – Regime Identification. The Advisor utilizes the output of the systematic model to determine the prevailing business cycleregime. Within the model, growth factors are used to measure economic growth conditions; liquidity factors are used to measure the credit cycle; and inflation factors are used to measure the direction of trend inflation. The identification of the prevailing business cycle regime determines the risk parameters and general asset allocation for the Fund.Step 2 – Return Estimation. The Advisor’s model systematically generates return estimates for a population of assets reflecting global equities, credit, core bonds, currencies, and commodities.Step 3 – Portfolio Construction. The Advisor conducts various portfolio optimizations using estimates for risk, correlation and returns, targeting the portfolio risk parameters identified as described in step 1 and using the returns identified in step 2.Step 4 – Qualitative Review of the Fund’s Portfolio. The Advisor adjusts portfolio positions to reflect discretionary analysis, including, but not limited to, valuation, sentiment, and sector fundamentals. The Fund’s portfolio managers balance the optimal portfolio identified solely based upon the systematic model against the opportunities identified through their discretionary analysis, subject to controlled ranges for deviation from the optimized portfolio in terms of relative volatility and tracking error. (Tracking error is a measure of the risk in an investment portfolio that is due to active management decisions.) The Advisor is also permitted to make broader changes to the asset allocation suggested by the systematic model but expects to do so only in limited situations. The resulting portfolio is then implemented by the Advisor by investing the Fund’s assets primarily in Underlying Funds.Because the Fund’s targeted risk is largely determined by the systematically identified regime, the Fund’s portfolio may at times be positioned defensively during risk-averse regimes. This may help the Fund’s portfolio to preserve capital during drawdowns. However, if assets such as equities and credit perform well during a risk-averse regime when the Fund’s portfolio is defensively positioned, the Fund’s portfolio may underperform relative to the broader market.The Advisor may sell a holding if the Advisor’s outlook on an asset class or sector changes or the Advisor identifies what it believes to be a more attractive investment opportunity. The portfolio will generally be rebalanced on a monthly basis, although the Advisor reserves the right to rebalance the portfolio at other times in response to market conditions.The Fund has wide flexibility in the relative weightings of asset classes and sectors and the Fund’s asset allocation can change significantly over time based on the Advisor’s outlook for the global economy and market conditions. The Fund may at times engage in active and frequent trading to achieve its principal investment strategies.

Bar Chart and Performance Table [Heading]

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Performance

Performance One Year or Less [Text]

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Because the Fund is newly organized and does not yet have a complete calendar year of performance history, the bar chart and total return tables are not provided.

Performance Availability Website Address [Text]

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harborcapital.com

Risk [Text Block]

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This means that you could lose money on your investment in the Fund or the Fund may not perform as well as other investment options.

Risk Return Abstract

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Risk [Text Block]

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Asset Allocation Risk: The Fund’s investment performance depends upon the successful allocation by the Advisor of the Fund’s assets among asset classes, geographical regions, sectors and specific investments. The Advisor’s judgment about the attractiveness, value and growth potential of a particular asset class, region, sector or investment may be incorrect and the Advisor’s selection of the Underlying Funds to implement its asset allocation decisions may not produce the desired results. The Advisor potentially will be prevented from executing investment decisions at an advantageous time or price as a result of domestic or global market disruptions, particularly disruptions causing heightened market volatility and reduced market liquidity, as well as increased or changing regulations.

Risk Return Abstract

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Risk [Text Block]

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Authorized Participant Concentration/Trading Risk: Only authorized participants (“APs”) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as APs and such APs have no obligation to submit creation or redemption orders. Consequently, there is no assurance that APs will establish or maintain an active trading market for the shares. This risk may be heightened to the extent that securities held by the Fund are traded outside a collateralized settlement system. In that case, APs may be required to post collateral on certain trades on an agency basis (i.e., on behalf of other market participants), which only a limited number of APs may be able to do. In addition, to the extent that APs exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other AP is able to step forward to create or redeem Creation Units (as defined below), this may result in a significantly diminished trading market for shares, and shares may be more likely to trade at a premium or discount to the Fund’s net asset value and to face trading halts and/or delisting. This risk may be heightened during periods of volatility or market disruptions.

Risk Return Abstract

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Risk [Text Block]

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Affiliated Fund Risk: The Advisor is subject to potential conflicts of interest in determining whether to invest in an underlying fund managed by the Advisor, and the Advisor may have an economic or other incentive to make or retain an investment in an affiliated fund in lieu of other investments that may also be appropriate for the Fund.

Risk Return Abstract

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Risk [Text Block]

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Credit Risk: The issuer or guarantor of a security owned by the Fund could default on its obligation to pay principal or interest or its credit rating could be downgraded. Likewise, a counterparty to a derivative or other contractual instrument owned by the Fund could default on its obligation. This risk may be higher for below investment-grade securities.

Risk Return Abstract

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Risk [Text Block]

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Emerging Market Risk: Because the Fund may invest in securities of emerging market issuers, an investment in the Fund may be subject to special risks in addition to those of U.S. securities. These risks include heightened political and economic risks, greater volatility, currency fluctuations, higher transaction costs, delayed settlement, possible foreign controls on investment, possible sanctions by governmental bodies of other countries and less stringent investor protection and disclosure standards of foreign markets. Foreign securities are sometimes less liquid and harder to value than securities of U.S. issuers. The securities markets of many foreign countries are relatively small, with a limited number of companies representing a small number of industries. If foreign securities are denominated and traded in a foreign currency, the value of the Fund’s foreign holdings can be affected by currency exchange rates and exchange control regulations. The Fund’s investments in foreign securities may also be subject to foreign withholding taxes.Foreign securities risks are more significant in emerging market countries. These countries may have relatively unstable governments and less-established market economies than developed countries. Emerging markets may face greater social, economic, regulatory and political uncertainties. These risks make emerging market securities more volatile and less liquid than securities issued in more developed countries. Securities exchanges in emerging markets may suspend listed securities from trading for substantially longer periods of time than exchanges in developed markets, including for periods of a year or longer. If the Fund is holding a suspended security, that security would become completely illiquid as the Fund would not be able to dispose of the security until the suspension is lifted. In such instances, it can also be difficult to determine an appropriate valuation for the security because of a lack of trading and uncertainty as to when trading may resume.Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market.

Risk Return Abstract

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Risk [Text Block]

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Fixed Income Security Risk: Fixed income securities fluctuate in price in response to various factors, including changes in interest rates, changes in market conditions and issuer-specific events.

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High-Yield Risk: There is a greater risk that the Fund will lose money because it invests in below investment-grade fixed income securities and unrated securities of similar credit quality (commonly referred to as “high-yield” or “junk” bonds). These securities are considered speculative because they have a higher risk of issuer default, are subject to greater price volatility and may be illiquid.

Risk Return Abstract

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Risk [Text Block]

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Mortgage- and Asset-Backed Securities Risk: Mortgage and other asset-backed securities in the Fund’s portfolio may have especially volatile prices because the embedded leverage can magnify the impact of the extension or contraction event on the underlying cash flow. Mortgage-related securities are also subject to prepayment and extension risks.

Risk Return Abstract

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Risk [Text Block]

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Quantitative Analysis Risk: There are limitations inherent in every quantitative model. The value of securities selected using quantitative analysis can react differently to issuer, political, market, and economic developments than the market as a whole or securities selected using only fundamental analysis. The factors used in quantitative analysis and the weight placed on those factors may not be predictive of a security’s value. In addition, historical trends in data may not be predictive going forward. The strategies and techniques employed in a quantitative model cannot fully match the complexity of the financial markets and therefore sudden unanticipated changes in underlying market conditions can significantly impact their performance. The effectiveness of the given strategy or technique may deteriorate in an unpredictable fashion for any number of reasons including, but not limited to, an increase in the amount of assets managed or the use of similar strategies or techniques by other market participants and/or market dynamic shifts over time. In addition, factors that affect a security’s value can change over time, and these changes may not be reflected in the quantitative model. Any model may contain flaws the existence and effect of which may be discovered only after the fact or not at all. There can be no assurances that the strategies pursued or the techniques implemented in the quantitative model will be profitable, and various market conditions may be materially less favorable to certain strategies than others. Even in the absence of flaws, a model may not perform as anticipated.

Risk Return Abstract

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Risk [Text Block]

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Sector Risk: To the extent that the Fund has significant exposure to a particular sector or commodity, the Fund will be subject to the risk that economic, political or other conditions that have a negative effect on that sector or commodity will negatively impact the Fund to a greater extent than if the Fund’s assets were invested in a wider variety of sectors or commodities.

Risk Return Abstract

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U.S. Government Securities Risk: Securities issued or guaranteed by U.S. government agencies or government-sponsored entities may not be backed by the full faith and credit of the U.S. government. As a result, no assurance can be given that the U.S. government will provide financial support to these securities or issuers (such as securities issued by the Federal National Mortgage Association, or the Federal Home Loan Mortgage Corporation). Although certain government securities are backed by the full faith and credit of the U.S. government (such as securities issued by the Government National Mortgage Association), circumstances could arise that would delay or prevent the payment of interest or principal. It is possible that issuers of U.S. government securities will not have the funds to meet their payment obligations in the future and, in these circumstances, the Fund’s returns may be adversely affected.

Risk Return Abstract

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Distribution and Service (12b-1) Fees

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none

Acquired Fund Fees and Expenses

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0.17%

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OneYear

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$ 89