Counties That Make Up the Salt Lake City Metro Area

The Salt Lake City metropolitan area spans multiple counties across north-central Utah, each contributing distinct geography, population, and economic function to the broader region. Understanding which counties belong to this metro area matters for purposes ranging from federal funding allocations to regional transportation planning and census data analysis. The composition of the metro area is defined by federal statistical standards and shifts when demographic and commuting patterns cross established thresholds.

Definition and scope

The Salt Lake City metropolitan statistical area (MSA) is formally defined by the United States Office of Management and Budget (OMB), which establishes and periodically updates MSA boundaries based on core urban concentrations and the counties economically integrated with them (U.S. Office of Management and Budget, OMB Bulletin 23-01). Under the 2023 OMB delineations, the Salt Lake City MSA is composed of 3 counties:

1. Salt Lake County — the urban core, seat of Salt Lake City, and the most densely populated county in Utah
2. Tooele County — located west of the Oquirrh Mountains, with growing residential development tied to Salt Lake employment centers
3. Davis County — situated immediately north of Salt Lake County along the Wasatch Front corridor

The broader Salt Lake City–Provo–Orem Combined Statistical Area (CSA) draws in additional counties from the Utah County corridor to the south, but those counties are grouped under the Provo–Orem MSA rather than the Salt Lake City MSA proper. The distinction between an MSA and a CSA is consequential: MSAs reflect tightly integrated labor markets, while CSAs describe looser economic linkages between adjacent MSAs.

For a detailed geographic treatment of how these boundaries are drawn and what physical features delineate them, the Salt Lake City Metro Boundaries and Geography page provides county-level mapping context.

How it works

OMB assigns counties to an MSA based on a principal city criterion and a commuting flow standard. A county qualifies for inclusion when a defined share of its working residents commute to the MSA's core county — or when inflow commuting from the core reaches the threshold. OMB applies a 25 percent commuting threshold as the primary standard, with secondary measures for employment interchange rates (U.S. Census Bureau, Metropolitan and Micropolitan Statistical Areas).

Within the Salt Lake City MSA, the three counties function as follows:

• Salt Lake County anchors the MSA as the principal county. It contains Salt Lake City (the principal city) and hosts the majority of the metro's employment base, government institutions, and infrastructure. The county's population exceeded 1.1 million as of the 2020 decennial census (U.S. Census Bureau, 2020 Census).
• Davis County qualifies through high commuting interchange with Salt Lake County. Cities such as Layton, Bountiful, and Clearfield send a large share of workers into Salt Lake County daily.
• Tooele County meets the commuting threshold from its eastern communities closest to the Salt Lake Valley, even though much of the county's land area is remote desert and military testing range.

Population data across all three counties, as well as demographic breakdowns by age, race, and household composition, are covered in the Salt Lake City Metro Population and Demographics reference.

Common scenarios

The three-county composition produces several practical situations that affect residents, planners, and businesses differently depending on which county they operate in.

County seat and municipal services: Each county maintains its own elected government, property tax authority, and service districts. Salt Lake County's seat is Salt Lake City. Davis County's seat is Farmington. Tooele County's seat is Tooele City. A business requiring permits must navigate the specific county government where the property is located, not a single metro-wide authority. The Salt Lake City Metro Government Structure page maps how these layers interrelate.

Transit network coverage: The Utah Transit Authority (UTA), which operates TRAX light rail and FrontRunner commuter rail, provides service across all 3 counties. FrontRunner's north-south spine connects Davis County stations (as far north as Ogden, which is in Weber County) through Salt Lake County. Tooele County has more limited fixed-route service. Coverage details are mapped on the Salt Lake City Metro Transit System page.

Air quality regulation: All three MSA counties fall under the Wasatch Front nonattainment area for fine particulate matter (PM2.5) under EPA standards. The Salt Lake City Metro Air Quality page explains how geographic basin conditions cause pollutant inversions that affect county-level regulatory obligations differently based on elevation and topography.

Decision boundaries

The county composition of the Salt Lake City MSA is not permanent. OMB revises MSA delineations following each decennial census, and intermediate updates can occur via published bulletins when commuting data or population thresholds change materially.

MSA vs. CSA distinction: Salt Lake County, Davis County, and Tooele County belong to the Salt Lake City MSA. Utah County (containing Provo and Orem) and Summit County are part of adjacent MSAs that, together with the Salt Lake City MSA, form the larger CSA. Using CSA-level data when MSA-level data is appropriate — or vice versa — produces significant errors in per-capita calculations, housing market analyses, or federal grant applications. For economic data tied specifically to the 3-county MSA, the Salt Lake City Metro Economic Profile provides the relevant figures.

Weber County: Weber County (seat: Ogden) is part of the Ogden–Clearfield MSA under current OMB delineations, not the Salt Lake City MSA, despite its position immediately north of Davis County on the Wasatch Front. Transit and highway connections between the two MSAs are strong, but federal statistical programs treat them as distinct labor markets. This boundary distinction affects how workforce and commuting statistics appear in federal reports.

Tooele County internal variation: The eastern portion of Tooele County — including Tooele City and Grantsville — drives the county's MSA inclusion. Western Tooele County, which encompasses the Bonneville Salt Flats and Dugway Proving Ground, has negligible residential population and no meaningful commuting pattern. Any analysis using county-level data for Tooele should account for this sharp internal geographic divide.

For the full index of metro area topics, the Salt Lake City Metro Authority home page provides a structured entry point to all regional reference resources.

References

• U.S. Office of Management and Budget, OMB Bulletin 23-01 — Revised Delineations of Metropolitan Statistical Areas
• U.S. Census Bureau — Metropolitan and Micropolitan Statistical Areas
• U.S. Census Bureau — 2020 Decennial Census Data
• Utah Transit Authority (UTA) — Service Area and Route Information
• U.S. Environmental Protection Agency — Nonattainment Areas for Criteria Pollutants (Green Book)