What Is PHO? Invesco Water Resources ETF

PHO is the Invesco Water Resources ETF, the largest and oldest water-themed ETF focused on US companies. It tracks the NASDAQ OMX US Water Index and holds roughly 40 firms that make money from conserving, purifying, testing, and moving water for homes, businesses, and industry. It launched in December 2005 as one of the first thematic ETFs.

The idea behind PHO is a long-run structural theme: growing water scarcity, aging pipe networks that need replacing, and tightening treatment standards should keep demand high for water infrastructure and equipment. PHO packages that thesis into a single ticker, though at a higher fee and with more concentration than a broad index fund.

Approximate weights as of mid-2026; refresh quarterly from Invesco's fund page. Each ticker links to its individual stock guide in Walnut.

PHO's holdings span the whole water value chain. There are regulated utilities like American Water Works, pipe and infrastructure distributors like Ferguson and Core & Main, and a large cluster of equipment, filtration, and testing companies including Waters, Roper Technologies, Ecolab, IDEX, Xylem, and Veralto.

The fund is fairly concentrated: roughly 40 holdings, with the top ten accounting for about 60% of assets. That means the equipment and industrial names, rather than pure water utilities, drive most of PHO's performance. Investors expecting a utility-like defensive fund are often surprised by how industrial the portfolio actually is.

The closest sibling is Invesco's own PIO, the Global Water ETF, which adds international water names like Veolia and Geberit and charges a higher 0.75%. PHO is the US-only, larger, and cheaper of the two. First Trust's FIW is another US water ETF that tracks a different index and weights its holdings differently, giving it a distinct sector tilt.

Choosing among them comes down to geography, cost, and index construction. PHO is the standard US pure-play, PIO globalizes the theme at a higher fee, and FIW offers an alternative US weighting. Comparing top holdings and expense ratios directly is the clearest way to decide.

PHO's returns track the fortunes of water-infrastructure and equipment companies, which are tied to construction activity, industrial capital spending, and municipal budgets. Because it is concentrated and industrial in character, it can be more volatile than the broad market and does not behave like a defensive utility fund.

The long-term case rests on durable demand drivers: replacing aging pipes, meeting stricter water-quality rules, and addressing scarcity in a warming climate. Those tailwinds are real but play out over years, so PHO is better suited to patient, theme-oriented investors than to those seeking steady income or low volatility.

PHO may fit investors who want targeted, long-run exposure to the water theme and are comfortable with a concentrated portfolio, a higher fee, and minimal income. It is best used as a thematic satellite alongside a diversified core, not as a standalone core holding.

Walnut is not an investment adviser. Whether PHO belongs in your portfolio depends on your conviction in the water theme, your risk tolerance, the 0.59% cost, and how much industrial and utility exposure you already carry through other funds or stocks.

PHO trades like any stock on major brokerages including Robinhood, Fidelity, Schwab, and Public, and many of them let you buy fractional shares so you can start with a small dollar amount. As the largest water ETF, it is liquid enough for most individual investors during market hours.

After buying PHO, you can connect your brokerage to Walnut to track it alongside your other positions, see how much of your portfolio the water theme represents, and monitor how it moves relative to the broad market and your other holdings.

ETFs are passive bundles; thematic baskets in Walnut let you concentrate within them. If you hold PHO as a core position, these are the themes you might layer on as satellites.

PHO is the go-to US pure-play on the water theme: infrastructure, treatment, and equipment names in one ticker. The 0.59% fee is high for an equity ETF and it is concentrated in about 40 industrial and utility stocks. It is best treated as a thematic satellite, not a core holding, for investors who want long-run exposure to water scarcity and aging infrastructure.

Whether PHO is worth buying today depends more on your time horizon and what you already hold than on any single call. We walk through valuation, concentration, and what would have to be true for it to outperform from here in is PHO a buy?

PHO yields ~0.4% as of mid-2026, paid by passing through the dividends of its underlying holdings. For the payout schedule, history, and how the distributions are taxed, see PHO dividend: yield and schedule.