OPEN vs Z: Which Is the Better Buy in 2026?

Same yardstick, side by side (as of August 2026). Valuation lined up like this is most meaningful for two names in the same corner of the market, which these are. Figures are approximate; verify before investing.

The metrics above tell you which is the marginally better business. The bigger risk for most people is not picking the slightly worse stock, it is over-concentrating. OPEN and Z share themes, so owning both, or adding either to what you already hold, can quietly push a large share of your portfolio into one bet.

This is the part a generic comparison page cannot answer, because it depends on what you own. Connect your brokerage and Walnut shows your real, combined OPEN and Z exposure, flags overlap with your existing positions, and tells you if adding one would tip you past a concentration you are comfortable with, read-only by default, with your login staying at your broker. Walnut is not an investment adviser.

Opendoor Technologies runs an iBuyer platform that lets people sell a home online in days rather than through a traditional listing. The company makes an algorithmic cash offer, buys the home directly, does light repairs and renovation, and resells it, aiming to earn a spread plus service fees on each transaction. Its margins live at the unit level: contribution margin measures what is left after the resale price, holding costs, and selling costs on the homes it moves. Because Opendoor takes ownership of inventory, it carries homes on its own balance sheet and finances them largely with non-recourse asset-backed debt, which makes its economics highly sensitive to how fast it can turn inventory and which direction home prices move.

Full OPEN guide

Zillow Group, Inc. operates the largest online real estate marketplace in the United States, drawing hundreds of millions of monthly visits across the Zillow, Trulia, and StreetEasy brands. Its business has three pillars. Residential (its For Sale core) connects home shoppers with agents, earning mostly through Premier Agent and Showcase. Rentals monetizes multifamily and single-family listings through advertising and lead generation. Mortgages, run through Zillow Home Loans, originates purchase loans and ties financing into search. Zillow is a marketplace and software company, not a homebuilder or iBuyer, so its revenue tracks how actively people transact rather than the value of homes it owns.

Full Z guide

Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.

• OPEN drivers: Leverage to a housing recovery; Asset-lighter, faster operating model.
• Z drivers: Housing super app and enhanced markets; Rentals as a growth engine.

A faster-growing, richer-valued name usually swings harder, so it suits a longer horizon and a higher tolerance for volatility; a steadier, more cash-generative business suits a more conservative or income-minded investor. The honest test is which set of risks you could hold through a drawdown: The bear case is substantial. For Z, the dominant risk is housing cyclicality: with existing-home sales near multi-decade lows on elevated mortgage rates, Zillow's Residential and Mortgages revenue depend on a depressed transaction market, and a further slowdown or rate shock could stall growth.

Pick OPEN if you believe its drivers more; Z if you believe its. Many investors hold both, but since they share themes, that is a concentrated bet, not diversification. Decide deliberately and check overlap. For the full detail, see the OPEN and Z guides.

OPEN. Opendoor trades as a speculative turnaround rather than on conventional earnings multiples, because it is not yet profitable and its results swing with housing activity. Revenue has fallen sharply from prior years as the company bought fewer homes, while unit-level margins have improved. Figures are approximate, drawn from the most recent reported quarter, and can change materially with each housing cycle and each new disclosure.

Z. These characterizations are qualitative and tied to the asOf date; verify live figures before acting. Zillow is best understood as a growth marketplace stock, so investors tend to weigh revenue growth, segment mix (Rentals and Mortgages versus Residential), and EBITDA margins more than a headline P/E, which can be distorted while the company transitions from GAAP losses to profits. Because there is no dividend, the entire return case rests on growth and eventual free cash flow rather than income.

Headline figures (approximate, 2026-06-27): OPEN shows revenue (ttm) ~$3.9B, q1 2026 revenue ~$720M, homes sold (q1 2026) ~1,921, contribution margin (q1 2026) ~4.4%; Z shows revenue trend Growing at a strong double-digit pace year over year in early 2026, led by Rentals and Mortgages with a steady Residential base, profitability Reached full-year GAAP profitability, a milestone after years of accounting losses; still reinvesting heavily in Rentals and Mortgages, margins Adjusted EBITDA margin has been expanding into the mid-20s percent range as the model scales; watch the trajectory, not a single quarter, dividend None; Zillow pays no dividend and returns capital mainly through share repurchases, so total return depends on price appreciation.

OPEN and Z are related but distinct: same themes, different businesses and risks. Neither wins in the abstract; the right pick is whichever thesis you actually believe, sized so you are not over-concentrated in one theme. Walnut can show your combined OPEN and Z exposure against your real portfolio. It is not an investment adviser.