Walnut vs Mezzi: Which Is Better in 2026?

Prices checked October 2026. A price marked (Oct 2026) was read on the vendor's own pricing page; others are described without a number because we could not verify one.

The AI that knows your portfolio. Ask anything in plain English, research any stock or fund, and get an honest second opinion, on the broker you already use. Read-only by default, you approve every trade, and it never holds your money. Walnut is not an investment adviser.

How it works: You connect the brokerage you already use, read-only by default, so your login stays with your broker and your money never moves. Walnut gives each holding a keep, trim or exit read from its one-year price return against the S&P 500, its momentum and its size, and flags any position above a quarter of the portfolio. You ask follow-up questions in Walnut's own assistant, or inside Claude or ChatGPT through its connector, which only reads. You can turn a thesis into a basket with target weights, and when you decide to act Walnut drafts the trades and places the ones you approve at Public plus eight other brokers including E*Trade, tastytrade and Webull.

In practice, Walnut’s AI reads your real holdings, rates each one against the S&P 500, builds baskets and drafts trades. It is an AI investing app that connects the brokerage you already use, best suited to a keep, trim or exit read on the stocks you already own, and placing the trades you approve. On connecting an account: yes (the brokerage you already use, read-only by default). On execution: places the trades you approve at Public and eight other brokers. Cost: free; Walnut Unlimited $9.99/mo on the web; no fee on assets.

One honest limitation: It has no cost basis or tax lots, so returns are one-year price returns rather than profit and loss, and it is read-only at Schwab, Fidelity and Vanguard.

Aggregates your accounts and layers AI insights with a tax-aware lens. Best for a consolidated view across holdings.

How it works: Mezzi aggregates your investment accounts into one view and layers AI insights over them with a tax-aware lens, flagging things like potential wash sales, fee drag, and unrealized-gain considerations across accounts. It is read-only: it tells you what it sees and what to consider, and you act at your broker.

In practice, Mezzi’s AI aggregates accounts + tax-aware insights. It is an AI investing app that connects the brokerage you already use, best suited to aggregated wealth tracking with AI. On connecting an account: yes. On execution: read. Cost: subscription.

One honest limitation: Tracking-and-insight focused rather than thesis-driven basket building.

The honest framing: Mezzi is about its own take on AI-assisted portfolio management, while Walnut is about a keep, trim or exit read on each holding, thematic baskets, its own assistant plus Claude and ChatGPT, and placing the trades you approve. Mezzi also connects your accounts; the difference is that Walnut goes from the read to the order, while it stops at the analysis.

Every tool gives something up for what it does well. Here is the honest give-and-take on each, so you can weigh the specific strengths against the limitations that come with them rather than judging on the headline category alone.

For AI investing tools, the distinction that matters most is whether the tool works from your actual, connected positions or reasons from something else: a separate account it manages for you, or the tickers and numbers you feed it. It decides how personal the answers can be, and where your money physically lives.

• Walnut: reads your real connected holdings. Walnut connects your real brokerage (Yes (the brokerage you already use, read-only by default)) and works from your actual positions, so its answers reflect what you genuinely own rather than a generic model.
• Mezzi: reads your real connected holdings. Mezzi connects your real brokerage (Yes) and works from your actual positions, so its answers reflect what you genuinely own rather than a generic model.

On this specific question the two land on the same side, so the deciding factors between them are elsewhere: category, cost, and who each is built for. This holdings-aware angle is the one Walnut is built around: it connects the brokerage you already use and reasons from your live positions, read-only by default, with any trades left for you to approve.

Each one wins a different job, so the answer is committed per job rather than overall.

• Choose Walnut if you want a keep, trim or exit read on the stocks you already own, and placing the trades you approve. Its AI reads your real holdings, rates each one against the S&P 500, builds baskets and drafts trades, and it costs free; Walnut Unlimited $9.99/mo on the web; no fee on assets. It is built for investors who already own stocks at a broker and want an AI investing app to tell them which to keep, trim or exit, without moving their money. Keep in mind: it has no cost basis or tax lots, so returns are one-year price returns rather than profit and loss, and it is read-only at Schwab, Fidelity and Vanguard.
• Choose Mezzi if you want aggregated wealth tracking with AI. Its AI aggregates accounts + tax-aware insights, and it costs subscription. It is built for multi-account investors who want tax-aware tracking and insights consolidated in one place. Keep in mind: tracking-and-insight focused rather than thesis-driven basket building.

Because both sit in the same category, the choice comes down to the finer details above rather than a fundamental difference in approach.

Cost is easy to misread when two tools charge in different shapes, so compare the model, not just the number. Walnut: free; Walnut Unlimited $9.99/mo on the web; no fee on assets. Mezzi: subscription. A percentage-of-assets fee scales with your balance, a flat subscription does not, and a “free” tier usually earns elsewhere (on cash, order flow, or premium upgrades), so the cheapest headline is not always the cheapest outcome for your situation.

Prices checked October 2026. Pricing and tiers change, so confirm the current numbers on each provider’s own site before you decide.