Does CoStar Real Estate Manager Do Lease Abstraction?

Yes, CoStar Real Estate Manager does lease abstraction, in two ways. CoStar runs a long-standing managed abstraction and data validation service where its teams read the leases and populate the fields for you. Separately, after CoStar acquired Visual Lease in a deal that closed in November 2024, Visual Lease offers AI-powered lease scanning marketed as powered by CoStar's Lease LLM. Both are sales-led rather than a free, self-serve tool.

That distinction matters if you are trying to get leases into CoStar quickly, or to test the quality of the abstraction before you commit. Here is how CoStar's abstraction actually works, what it costs you in time and process, and where a free abstraction layer fits.

CoStar's managed abstraction service

CoStar has one of the longer track records in lease abstraction, document management, and data validation. Its managed service is the traditional model: you hand over the leases, CoStar's teams abstract them into your CoStar Real Estate Manager fields and validate the data, and you receive a populated system. This fits a large one-time migration where you would rather outsource the reading entirely and want a vendor to stand behind the accuracy. The tradeoff is that it runs on the vendor's schedule and pricing, and it is an engagement you scope and buy, not something you can try on a single lease this afternoon.

CoStar's AI abstraction through Visual Lease

The AI side came with Visual Lease. Visual Lease markets AI-powered lease scanning and abstraction built with CoStar's in-house abstractors and attorneys, with output validated against CoStar's proprietary property and market data through dozens of benchmarks, and a stated policy that customer data is not used to train the models. It is a genuine AI abstraction capability. The catch for a buyer evaluating it is access: it is part of the Visual Lease and CoStar platform, so you engage sales or buy the platform first. There is no free front door where you upload one lease and judge the result.

What CoStar abstraction captures

Whether human or AI, abstraction for CoStar targets the fields the accounting engine runs on: possession, commencement, and rent start dates; the full stepped base rent schedule; renewal, termination, and purchase options with their notice dates; and the CAM and operating expense recovery terms. These are the same fields any lease abstract should capture, and the accuracy that matters most sits on the dates and the rent schedule, because CoStar builds its ASC 842 calculations directly from them. A wrong commencement date is not a typo in CoStar; it is a wrong schedule.

How to test abstraction quality before you commit

The honest way to judge any lease abstraction, CoStar's included, is to run your own worst-scanned lease through it and check the fields that drive the accounting. Confirm the commencement date, the first and last rent steps, and one option notice date against the document. Every accuracy figure published in this category is self-reported, so a vendor's headline number tells you less than one bad lease abstracted in front of you. Because CoStar's options are sales-led, the practical way to run that test today is with a free tool. You can abstract a lease for CoStar and see every field cited to its source page using the tool at the top of the page, then decide whether you also want CoStar's managed service on top.

Where an independent abstraction layer fits

CoStar Real Estate Manager is the system of record for lease administration and accounting, and nothing here replaces what it does with the data once it is loaded. What an independent abstraction layer adds is speed and a way to verify: upload any lease, get the CoStar fields as source-linked structured data in minutes, review against the clause, and export a file ready for CoStar's import tool. It works whether you are migrating a portfolio into CoStar for the first time or adding new leases to an existing instance. The same engine handles the whole portfolio through the lease abstraction software, including the critical date extraction CoStar keys its alerts off. On the finance side, lenders underwriting a property against that lease income can run the borrower and property documents through automated loan underwriting analysis from the same abstracted data.

How CoStar abstraction compares to the alternatives

There are really three ways to abstract leases for CoStar, and they trade off control against effort. Manual abstraction, staff reading each lease and keying the fields, is the most flexible and the slowest, and it is where most keying errors enter. CoStar's managed service moves the labor and the accountability to the vendor, which suits a one-time migration but runs on the vendor's clock. Self-serve AI abstraction sits in between: you keep control and get results in minutes, and you review the output yourself against each source page. For a portfolio of any size, most teams end up combining them, using AI to do the bulk read and a human to review the high-stakes fields, rather than paying for a full managed engagement or keying everything by hand.

Does CoStar abstraction cover renewals and amendments?

It has to, because a lease is rarely just the original document. A commercial lease that has run for years carries amendments that change the rent, exercised options that extend the term, and side letters that adjust the recovery terms, and an abstract that reads only the base lease will feed CoStar the wrong current state. CoStar's managed abstractors work through the full file, and a capable AI tool should be given every amendment alongside the base lease so the fields it returns reflect the lease as it stands today, not as it was signed. When you test any abstraction, use a lease with at least one amendment and confirm that the current rent and term reflect the amendment, not the original.

So does CoStar do lease abstraction, or not?

It does, both by hand and with AI, but not in a form you can try free or self-serve. If you already run CoStar or are buying it, its managed service and Visual Lease AI abstraction are real options for a large migration. If you want to abstract a lease right now, verify the fields yourself, and load CoStar without waiting on an engagement, an independent tool gets you there faster. For how the load itself works, see how to import lease data into CoStar Real Estate Manager.