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Research/Chicago/One South Dearborn
Public SeedReviewed August 13, 2026

One South Dearborn

1 S Dearborn St, Chicago, IL 60603

QUALITY STATE

86% provisional source coverage

USE BOUNDARY

Not verified · Not dispatch ready

Direct answer

One South Dearborn is a commercial office tower at 1 S Dearborn Street in Chicago. Factum resolved it as one physical building, completed in 2005, with 40 stories and a City-reported 2023 gross floor area of 942,732 square feet. The public record is graph mapped with 86% provisional critical-field coverage, but it is not independently verified or dispatch ready.

Completed2005Published property record
Stories40Published building identity
Critical fields sourced19/2286% provisional coverage
Dispatch readyNoLive accuracy audit required
01

Canonical identity

The public-source record resolves building identity, management, major delivery and move routing, service-elevator topology, insurance requirements, vendor access, work-order systems, and telecommunications-riser coordination. Unlike area claims remain separate rather than being flattened into one number.

Property typeOffice
Management routeHines is the published management route.
Ownership claimThe official property portal attributes ownership to Starwood Capital Group and Vanderbilt Properties; ownership is time-sensitive and should be rechecked before use.
Location41.88165, -87.62885
02

Area claims stay separate

Gross, rentable, and office area are not interchangeable. Factum stores each measurement with its source meaning instead of choosing a convenient single number.

City-reported gross floor area942,732 sq ftData year 2023
Rentable area829,000 sq ftCurrent leasing presentation; different predicate
Office space820,915 sq ftOfficial property portal; different predicate
03

What public guidance supports

These are sourced research answers, not permission to enter, reserve, submit, or dispatch. Current affected-party authorization remains required.

Delivery route

The official property portal routes deliveries through the loading dock and service elevators rather than the main lobby or passenger elevators.

Live property portal captured 2026-08-11

Loading dock

The published dock is on the south side of the building and is reached from Dearborn Street through the east–west alley. The portal describes three loading bays.

Live property portal captured 2026-08-11

Freight movement

Two published service elevators connect the dock, mezzanine, and floors 2–39. Reservations and current operating constraints must be confirmed with management before a job.

Live property portal captured 2026-08-11

Move scheduling

An official but undated move-guidelines PDF publishes weekday early-morning or evening windows and weekend availability. Because the document has no visible effective date, Factum treats this as a medium-confidence claim requiring confirmation.

Undated first-party PDF captured 2026-08-11

Telecommunications

The property portal identifies IMG Technologies as the building-riser coordination route and publishes an advance-access procedure. Current timing and pricing remain confirmation items.

Live property portal captured 2026-08-11
04

Questions this record answers

Each concise answer includes the same caveats shown elsewhere on the page.

01What is One South Dearborn?+

One South Dearborn is a 40-story commercial office tower completed in 2005 at 1 S Dearborn Street in Chicago’s Loop.

02Where should deliveries enter One South Dearborn?+

The building’s published guidance routes deliveries through the south-side loading dock and service elevators, not the lobby or passenger elevators. Job-specific access still requires current confirmation and authorization.

03How large is One South Dearborn?+

Different sources describe different area concepts: 942,732 square feet of City-reported gross floor area for data year 2023, 829,000 square feet of rentable area, and 820,915 square feet of office space. Factum preserves these as separate claims.

04Can this record be used to dispatch a job?+

No. The record is graph mapped but not independently verified or dispatch ready. Current management confirmation, authorization, and a live-job accuracy audit are still required.

05How can a building team correct this record?+

Join Factum early access and send a correction, current handbook, link, forwarded email, or a few notes. Factum does not ask for credentials or sensitive security information.

05

Explicit unknowns

Anything operationally material that is stale, incomplete, or unconfirmed remains visible here.

  1. 01Effective and revision dates for the move guidelines and published property-team directory.
  2. 02Current certificate-holder and additional-insured requirements for vendor insurance.
  3. 03Current rates, cancellation terms, blackout dates, and staffing rules for billable services.
  4. 04Detailed current contractor procedures for construction, low voltage, hot work, shutdowns, permits, staging, and disposal.
  5. 05Live-job accuracy audit and affected-party confirmation of dispatch-critical fields.
06

Evidence register

Source links are direct. Authority and supported claim groups are stated so readers can inspect the underlying record.

  1. 01
    About One South Dearborn ↗

    Official property portal · Supports: Building identity, area, ownership claims

  2. 02
    Loading Dock & Service Elevators ↗

    Official property portal · Supports: Published delivery, dock, and service-elevator guidance

  3. 03
    Tenant Move Rules ↗

    Official property PDF · Supports: Move, insurance, labor, and protection claims; document is undated

  4. 04
    Telecommunications ↗

    Official property portal · Supports: Riser management and coordination path

  5. 05
    Chicago Energy Benchmarking Results ↗

    City of Chicago · Supports: 2023 City-reported gross floor area and source identity

  6. 06
    One South Dearborn leasing ↗

    Current property leasing presentation · Supports: Rentable-area claim