Blog · October 14, 2026 · California
Mill Valley GIS Map: looking up parcels
Parcel data for this town comes from the county, and the viewer is free, at least around San Rafael.
Main page: Marin County, CA GIS & Parcel Viewer (official map link, county facts and neighboring maps).
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For a parcel in or near Mill Valley, the Mill Valley GIS map shows the outline, the owner of record and a parcel ID. What this town guide covers: where that map lives, how to search it, and what to double-check with records, at least around Larkspur.
Finding a lot on the Mill Valley GIS map
Some cities also run their own GIS portal for utilities or zoning; check the Mill Valley website for one.
Where the parcel data lives
Begin with the Marin County parcel viewer; it maps each assessed parcel from Belvedere to Corte Madera. For a home near Belvedere, enter a street address, an owner's name or a parcel number, and the viewer zooms to the match. Out toward Tiburon, write down the parcel ID before closing the panel; every records desk in the county uses it to find the file.
Sections, lots and bearings
California is laid out under the Public Land Survey System, which means a tract near Larkspur is described by section, township and range. A standard section is about one square mile, roughly 640 acres, and a township holds 36 of them, though corrections make some sections near Sausalito odd-sized. Write down the legal description for the tract near Belvedere for any title or survey request.
City limits and county records
Mill Valley lies within Marin County, California, and the county assessor maps its lots. With a lot near Sausalito, city or town hall handles matters such as zoning, permits and utilities within town limits, while the county keeps the tax map. Lots just outside the town limits out by Corte Madera generally answers to county rules, not municipal ones.
Finding the right lot
For a house in Mill Valley, search the street address; owner names are usually entered last name first. For acreage around Sausalito, searching by parcel number never misses, and it's printed on tax bills.
Limits of the parcel data
Parcel lines are drawn for taxes, not surveyed, so the edge of a yard near Ross often sits several feet off the line on screen. For a parcel near Corte Madera, owner names and values update on a schedule, so a deed recorded last month may not show yet.
Saving what you find
Save a screenshot of the lot near Ross and its record panel, which helps later when you ask the assessor or a title company.
Layers worth turning on
Switch to the aerial basemap over Mill Valley to compare lines with fences and driveways.
Getting answers from the right desk
Deeds, mortgages and recorded plats for land near Sausalito come from the County Recorder, often with an online index. Zoning, permits and septic questions near Ross are for the local planning and health departments, town or county, depending on location.
Deeds, plats and who keeps them
The map is an index, not the title: recorded deeds, plats and easements covering ground around Sausalito sit with the County Recorder. Near Ross, have ready the book and page from the tax record so staff can find the deed fast.
When a parcel crosses a boundary
Marin County meets Contra Costa County, San Francisco County, Solano County, and Sonoma County, and each of those keeps its own parcel map. A tract near the line by Larkspur can be split across two assessors' files, so open the neighboring map before you assume the acreage. For property near Ross, our state page links each neighboring county map across California.
Field tips
Most viewers work in a phone browser, useful out on a road near Belvedere, but coverage can be spotty out of town. A saved image of the lot near Corte Madera and its lines keeps working without signal.
Reading a parcel record
Sales history, if listed, helps with pricing near Larkspur are a useful starting point; an appraiser is the real authority.
Browser tips
When the map won't open around Sausalito, switch browsers or turn off pop-up blockers; the Platbookmapper county page tracks the current link.
Marin County in a few facts
San Rafael serves as the county seat, home to the main records offices. You'll also find Larkspur, Corte Madera, Ross, and Sausalito. Roughly 254,407 people call Marin County home (Census Bureau estimate, 2023) across some 520 square miles. Features like San Pablo Bay, San Francisco Bay, and Golden Gate National Recreation Area make handy reference points on the map near Ross.
Quick answers
Can I look up a property owner on the map near Larkspur?
Short answer: the parcel record for a lot near Tiburon lists the owner of record; try variations if nothing comes up.
How current is the parcel data for land near Corte Madera?
For most people, owner data near Tiburon can lag new deeds by weeks.
What layers does the parcel viewer have in Mill Valley?
If you're looking near Sausalito, many viewers offer aerial imagery plus layers like city limits, zoning or flood zones; availability varies.
Does the Mill Valley parcel viewer cost anything?
Short answer: the county viewer covering Mill Valley needs no account, though printing may be limited.
How is land described in California deeds in Mill Valley?
Closer to Ross, deeds use lot and block, metes and bounds or survey descriptions, and the parcel record often summarizes it.
Open the official Marin County, CA parcel map See it in the Platbookmapper directory
Not a survey. County GIS and tax parcel maps are assessment and planning layers. They are not a substitute for a recorded plat, deed, or licensed survey, especially for fences, setbacks, or boundary disputes.