Reonomy vs CompStak: Ownership Data vs Lease Comps (2026)

If you're evaluating Reonomy against CompStak, the first thing to understand is that you're usually not choosing between two versions of the same thing. They sit on different data layers of the acquisitions workflow. Reonomy answers who owns this asset and how do I reach the decision-maker? CompStak answers what are tenants in this submarket actually paying, and on what terms? One feeds your sourcing and outreach. The other feeds your underwriting and valuation.

That's why the honest answer to "Reonomy or CompStak?" is frequently "both, for different jobs." But budgets are finite and the data gap you're trying to fill is specific, so this guide is built to help you name the right tool for your bottleneck — and to be straight about the licensing realities of both, which materially affect how you can use them.

A note on positioning: NextAutomation is not a data vendor and doesn't compete with either of these tools. We're the AI/automation layer that operationalizes the data you license — blending ownership intelligence and lease comps into a single sourcing-to-underwriting pipeline. We'll tell you plainly which tool wins each use-case, and where automation makes whichever one you pick more valuable.

Head-to-Head at a Glance

The single sentence to remember: Reonomy gets you to the owner; CompStak gets you the rent. If your deals are dying because you can't find off-market owners, that's a Reonomy problem. If your deals are dying because your rent assumptions get challenged in IC, that's a CompStak problem.

Buyer Decision Criteria: Which Gap Are You Filling?

Before you compare features, diagnose the gap. Acquisitions and research teams reach for these tools for very different reasons, and buying the wrong one means paying for data you won't operationalize.

Reach for Reonomy when your gap is sourcing and outreach

Reonomy's value is ownership resolution — unmasking the entity behind a property, identifying the principals, and surfacing contact pathways so your team can run direct off-market outreach. If you're a principal or acquisitions lead whose pipeline depends on getting to owners before a broker does, ownership and contact data is the layer that feeds your top of funnel. Reonomy also carries debt and transaction history that helps you time outreach (e.g., loans approaching maturity).

Its limitation: ownership and contact data is inherently noisier than transaction data. Records age, entities restructure, and contact details require verification. Treat it as a high-quality sourcing input that still needs a verification step before outreach — not gospel.

Reach for CompStak when your gap is underwriting credibility

CompStak's value is real lease economics: actual starting rents, escalations, free rent, TI allowances, and lease terms — the concessions that asking rents hide. For an analyst defending a market-rent assumption in front of an investment committee, transaction-level comps are far more defensible than a broker's asking-rent quote. If your underwriting keeps getting picked apart on rent and concession assumptions, CompStak closes that gap.

Its limitation is structural: CompStak is a contribution marketplace. Coverage is deepest where active brokers and analysts contribute — major metros and office/retail/industrial — and thinner in secondary markets and some niche asset classes. Your access is also tied to the contribution/subscription model, which shapes both cost and what you can do with the data.

Honest Head-to-Head: Who Wins Each Use-Case

Neither tool is "better" in the abstract. Here's the objective call by use-case, naming a real winner each time.

• Off-market sourcing and owner outreach — winner: Reonomy. CompStak isn't built for this. If you need to find and contact owners, this isn't close.
• Defensible market-rent and concession assumptions — winner: CompStak. Transaction-level lease comps beat ownership records for underwriting. Reonomy doesn't compete here.
• National multi-asset-class property research — winner: Reonomy. Broader property-universe coverage across all CRE types.
• Office/retail/industrial valuation in major metros — winner: CompStak. The crowdsourced comp depth in primary markets is its core strength.
• Timing outreach to debt maturities — winner: Reonomy. Loan and transaction history is part of the ownership layer.
• Validating an IC memo's rent roll against the market — winner: CompStak. Real signed-lease terms are the gold standard for this check.

When to run both: a disciplined acquisitions shop uses Reonomy to find and reach the owner of an off-market asset, then CompStak to underwrite what that asset is worth based on real lease economics in the submarket. The two tools cover the front and middle of the same deal — they're complementary far more often than they're substitutes. The friction is that they're two separate subscriptions, two separate data formats, and two separate logins, with nothing stitching the ownership record to the comp set.

A Word on Licensing (Read This Before You Build Anything)

Both platforms are customer-licensed with redistribution restrictions, and this directly constrains how you can use their data in automations. Be honest about it up front so you don't build something you can't legally run.

Reonomy (now part of Altus Group) provides ownership and property data under license. Its API is partner-gated, and redistribution of the underlying data is restricted — you access it as a licensed customer, you don't resell or re-publish it.

CompStak runs a contribution model: brokers and analysts submit comps in exchange for credits, and the resulting dataset is shared back to the community under license. Because the data is contributed and licensed, comps cannot be redistributed, and your access is tied to your subscription and contribution. Any automation must respect that you're a licensed consumer of the data — it stays inside your own systems, used for your own deals. This isn't a NextAutomation limitation; it's how both vendors' agreements work, and any tool claiming to "redistribute" or "resell" Reonomy or CompStak data is misrepresenting what's permitted. See our Reonomy integration and CompStak integration pages for connection details under your own license.

Where AI Changes the Answer

The real problem isn't "Reonomy or CompStak" — it's that ownership data and lease comps live in separate silos, and the work of connecting them is manual. An analyst pulls the owner from one tool, the comps from another, normalizes formats by hand, and re-keys everything into the underwriting model. That stitching is exactly where an AI enrichment layer earns its keep.

A property-enrichment pipeline takes a target property, resolves the ownership and contact layer (from your licensed Reonomy data), pulls and normalizes the relevant lease comps (from your licensed CompStak data), and assembles a single enriched record — owner, debt timing, real submarket rents, and concessions — ready for outreach and underwriting. Instead of two tools and a spreadsheet, you get one workflow. The automation reads outputs from data you already license and keeps everything inside your systems, respecting both vendors' redistribution terms.

From there, an AI underwriting copilot uses the blended record to pre-fill the model: it drops the normalized comps into your rent and concession assumptions and flags where the in-place rents diverge from the market. The analyst spends time stress-testing the deal, not chasing data across two subscriptions. The key principle, same as everywhere in our stack: the AI sits on top of the tools you've licensed — it doesn't replace Reonomy or CompStak, and it doesn't move their data anywhere it isn't allowed to go.

Lifecycle Fit: Where Each Tool Earns Its Subscription

Mapped to the deal lifecycle, the division of labor is clean — and it's why most active acquisitions teams justify both line items.

• Sourcing: Reonomy owns this stage — property research, ownership unmasking, and contact data to drive off-market outreach. Pair it with an AI deal-sourcing agent that monitors signals and scores targets before you spend a credit looking them up.
• Underwriting: CompStak owns this stage — real lease comps anchor your rent and concession assumptions. The enrichment pipeline pre-loads those comps into the model so the analyst starts from market truth, not a blank cell.
• IC & Diligence: CompStak's transaction-level comps are the defensibility layer when the committee challenges your assumptions; Reonomy's ownership and debt history supports the deal narrative on motivation and timing.
• Asset Management: CompStak comps continue to inform lease renewals and mark-to-market on rollover; Reonomy helps track ownership changes across the surrounding submarket for future sourcing.

If you want to map which of these stages your firm is actually losing time on — and whether the answer is more data, better data, or just connecting the data you already pay for — our free roadmap call is the place to start.

Where This Fits in the Broader Stack

Reonomy and CompStak both live in the sourcing-and-market-data layer of the CRE stack, alongside CoStar, Crexi, Cherre, and ATTOM. For a full comparison of the data and comps landscape — including which platforms cover ownership, listings, comps, and unification — see our deep dive: Best CRE market-data and comps platforms.

And to see how this data layer connects to underwriting, deal management, property accounting, and investor reporting across your whole firm, read the pillar guide: The complete CRE software stack.