Property profile

425 Mason St San Francisco, CA 94102

OFF-MARKET
Office buildings
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Property ID
US09-6146840
36,720 SF 0.11 ac Built 1922
Last sale Dec 2019·$18,100,000
Entity Owned Owner of record is a legal entity (LLC / corporation). 6-yr Hold Held for 6 years. Absentee Owner Owner mailing address differs from the property address. ~ Est. High Equity Modeled equity is high. Estimate, not a fact.
Market Trends Soon

Property summary

AI-generated overview

This exceptional creative office building, located at 425 Mason Street in San Francisco's vibrant Union Square submarket, offers 40,123 square feet of vacant space, perfect for owner-users or investors. Built in 1922, this property boasts a rich history and unique character, complemented by modern amenities. The building is zoned C-3-G (Downtown General Commercial) and features multiple tenancy options, with spaces ranging from a minimum of 2,947 square feet to a maximum contiguous space of…

Ownership intelligence

Who controls the opportunity?

Owner of record from public deeds, plus portfolio, hold profile and investor signals where the data supports them. Included with a plan.

Owner contacts

Can we reach the decision maker?

Skip-traced phones and e-mails of the owner. Included with a plan.

Debts

What is owed, to whom, and when it comes due

Recorded lenders, amounts and estimated maturities of the owner's loan book — included with a plan.

Property tax · 2024

What does the county charge?
$248k
Tax billed · 2024
Assessed value$19.41M
Assessed land$12.61M
Assessed improvement$6.79M
Effective rate1.28%

Value estimate

· Nov 2026
$14.57M
$13.11M – $16.02M
CAP approach$14.85M
Submarket $/SF estimate$16.52M

Realmo valuation models over county records.

Recently sold

What actually traded nearby?
$542/SF
ZIP average, outlier-cleaned · 47 recorded sales of this use type
Observed band · Q1–Q3$379 – $753

Cap rate analysis

How does the asset earn?

No income signal is modeled for this parcel yet — the Cap Rates tab runs the workflow.

Zoning insight

What can be built here?
C3G
JurisdictionSAN FRANCISCO

Location intelligence

Which uses thrive at this corner?
Best fit: Buffet
Demand heat for this use is drawn on the map · LocInt grid
Demand index
Buffet6.2
Carpet & Flooring Store6.2
Pet Grooming Service5.3

Location

425 Mason St San Francisco, CA 94102-1722
County assessor Recorded deeds · 69 transfers Qualifying comp sales · not on file Zoning catalog

Every figure names its source: public record, benchmark, or modeled. Coverage varies by property — thin data is stated as missing, never invented.

Comparables

6 recorded sales · 15 properties nearby
Recent sales nearby
6 recorded sales in this ZIP, last 8 years
Address Sale price Sold Size
1240 Market, San Francisco, CA 94102-4801 $1,800,000 Dec 2024 10,780 SF
131 Franklin, San Francisco, CA 94102-6016 $6,300,000 Dec 2023 9,580 SF
436 Ofarrell, San Francisco, CA 94102-2010 $515,000 Jan 2023 9,709 SF
1930 Market, San Francisco, CA 94102-6228 $4,500,000 Aug 2021 14,800 SF
459 Fulton, San Francisco, CA 94102-4318 $935,000 Oct 2020 17,544 SF
Sale prices and dates as our records hold them, one row per building. A deed can cover more of a building than the size shown, so read the price against the size rather than dividing one by the other.
Comparable nearby
6 properties of the same type nearby
Research This Page with AI

Rey answers here. ChatGPT, Grok and Claude get the same data packet.

Includes: Price & PSF · Cap rate · Location · Zoning

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