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HARBOR ETF TRUST

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Harbor Osmosis International Resource Efficient ETF Fund Summary

Objective, Primary [Text Block]

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The Fund seeks long-term growth of capital.

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” 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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The Fund seeks to achieve its investment objective through active exposures to equity securities of resource efficient large- and mid-capitalization public companies across developed market countries, excluding the United States. The Fund defines resource efficient public companies as those that, relative to their sector peers, emit less carbon, consume less water and generate less waste, as discussed in more detail below.The quantitative strategy used by Osmosis Investment Management US LLC (the “Subadvisor”) in managing the Fund is predicated on its theory that resource efficiency, as measured by its proprietary Resource Efficiency Scores, is a predictor of which companies will generate investment returns above those of the MSCI World ex US Index (the Fund’s “Benchmark”). The outcomes of the Subadvisor’s theory are not guaranteed. Companies are scored relative to other companies in their respective sector with respect to their publicly reported carbon emissions, water use and waste production (including hazardous, non-hazardous or nuclear waste, which may be recycled incinerated or landfilled) in order to produce scores that are comparable across sectors. The Subadvisor maintains a database of proprietary environmental information and collects, verifies and standardizes data for use in calculating proprietary Resource Efficiency Scores. The process for linking environmental and financial factors is subject to ongoing research and enhancement by the Subadvisor. Portfolio holdings and weights are determined by an optimization process that seeks to maximize portfolio exposure to resource efficient companies (as determined by the Resource Efficiency Scores) while maintaining country, sector and factor (such as quality, volatility, leverage and earnings yield) weightings relative to the Fund’s Benchmark. Companies in the Financials sector are not given Resource Efficiency Scores due to their relatively minimal carbon emissions, water consumption and waste generation relative to other types of companies. Such companies are selected for inclusion in the Fund’s portfolio to maintain the portfolio’s overall factor weightings. Under normal circumstances, the Fund invests at least 80% of its net assets, plus borrowings for investment purposes, in resource efficient companies, which the Fund defines as companies included in the Benchmark with Resource Efficiency Scores in the top three quintiles when ranked against other scored companies within the applicable sector (provided that companies within the Financials sector are considered to be resource efficient for purposes of this policy solely based on their sector classification). The Fund may also invest up to 20% of its net assets in investments that the Subadvisor may not consider resource efficient in order to maintain weights relative to the Fund’s Benchmark, including when it is impractical or difficult to obtain such exposures through resource efficient companies. Such investments are outside the Fund’s 80% investment policy. The Fund typically holds securities of approximately 70 to 90 companies. The Fund does not invest in tobacco companies, companies engaged in the manufacture of cluster munitions or anti-personnel mines, or companies that breach the United Nations Global Compact’s social and governance safeguards (which are companies that do not act in accordance with the United Nations Global Compact’s principles and their associated standards, conventions and treaties). The Fund may invest in instruments denominated in U.S. dollars and foreign currencies. The Subadvisor utilizes the quantitative strategy described above to make its assessments and, except in very limited circumstances, follows the output of its strategy when making buy and sell decisions for the Fund’s portfolio. The Fund’s portfolio is rebalanced monthly.

Bar Chart and Performance Table [Heading]

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Performance

Performance One Year or Less [Text]

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Because the Fund 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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Resource Efficiency Strategy Risk: The theories and assumptions upon which the Subadvisor bases the methodology—including its resource efficiency scoring process—used in evaluating companies for the Fund may be unsound. A company’s business practices, products or services may change over time, as a result of which the Fund may temporarily hold securities that are inconsistent with its investment criteria. There is no guarantee that the Subadvisor’s methodology will accurately provide exposure to resource efficient companies. The Fund may outperform or underperform other funds that invest in similar asset classes but employ different investment styles. The Subadvisor’s strategy may result in the Fund investing in companies, industries or sectors that the market may not favor or foregoing investments that outperform the Fund’s investments in certain environments.

Risk Return Abstract

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Risk [Text Block]

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Market Risk: Securities markets are volatile and can decline significantly in response to adverse market, economic, political, regulatory or other developments, which may lower the value of securities held by the Fund, sometimes rapidly or unpredictably. Events such as war, acts of terrorism, social unrest, natural disasters, recessions, inflation, rapid interest rate changes, supply chain disruptions, sanctions, the spread of infectious illness or other public health threats could also significantly impact the Fund and its investments.

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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Cash Transactions Risk: The Fund will effect some or all of its creations and redemptions for cash rather than in-kind. As a result, an investment in the Fund may be less tax-efficient than an investment in an ETF that effects all of its creations and redemptions in-kind. Because the Fund may effect redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of portfolio securities may result in capital gains or losses and may also result in higher brokerage costs. To the extent costs are not offset by transaction fees charged by the Fund to APs, the costs of cash transactions will be borne by the Fund.

Risk Return Abstract

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Risk [Text Block]

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Geographic Focus Risk: The Fund may invest a substantial amount of its assets in securities of issuers located in a single country or geographic region. As a result, any changes to the regulatory, political, social or economic conditions in such country or geographic region will generally have greater impact on the Fund than such changes would have on a more geographically diversified fund and may result in increased volatility and greater losses.

Risk Return Abstract

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Risk [Text Block]

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Large Cap Risk: Large cap stocks may fall out of favor relative to small or mid cap stocks, which may cause the Fund to underperform other equity funds that focus on small or mid cap stocks. Large cap companies may be less able than smaller cap companies to adapt to changing market conditions and may be more mature and subject to more limited growth potential than smaller cap companies.

Risk Return Abstract

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Risk [Text Block]

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Mid Cap Risk: The Fund’s performance may be more volatile because it invests in mid cap stocks. Mid cap companies may have limited product lines, markets and financial resources. Securities of mid cap companies are usually less stable in price and less liquid than those of larger, more established companies. Additionally, mid cap stocks may fall out of favor relative to small or large cap stocks, which may cause the Fund to underperform other equity funds that focus on small or large cap stocks.

Risk Return Abstract

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Risk [Text Block]

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New Fund Risk: There can be no assurance that the Fund will grow to or maintain an economically viable size, in which case the Board of Trustees may determine to liquidate the Fund. The Board of Trustees may liquidate the Fund at any time in accordance with the Declaration of Trust and governing law. As a result, the timing of the Fund’s liquidation may not be favorable.

Risk Return Abstract

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Management Fees

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0.55%

Other Expenses,

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none

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OneYear

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$ 56