Philadelphia Zoning Districts

A plain-language guide to the zoning categories you'll encounter in development coverage

Based on Title 14, Philadelphia Code · City Quick Guide (PDF) ↗ · Anastasio Law Guide ↗ · Full District Reference →

Philadelphia's zoning code divides every parcel in the city into a base zoning district that determines what can be built there and how big it can be. Districts are organized into families that share a common logic, and numbered to signal intensity — higher numbers generally mean more density, more height, and more uses allowed.

Two families dominate development coverage: the residential family (RSA, RSD, RTA, RM) for primarily housing uses, and the commercial mixed-use family (CMX) for corridors and nodes that blend housing with retail and offices. There's also an industrial family (I-1 through I-3, IRMX, ICMX) that covers everything from light fabrication shops to port facilities.

What's actually allowed on any given parcel depends on the base district plus any overlay districts layered on top — and overlays can restrict or expand what the base district permits. The most common overlays you'll encounter in Philadelphia coverage are the /TOD (transit-oriented development), /NCO (neighborhood conservation), /MIN (mixed-income neighborhoods), and /CDO (Central Delaware Riverfront). See the Key Terms glossary for definitions of each.

How to read the code

RSA-5 Row houses. Most of Philadelphia's older residential fabric.
RM-1 Low-rise multifamily. Duplexes to small apartment buildings.
CMX-2 Neighborhood commercial corridor. Corner stores to mixed-use rowhouses.
CMX-3 Mid-rise mixed use. Where most urban apartment projects land.
CMX-5 Center City high-rise. Skyscrapers and towers.
/TOD Overlay: applied on top of any base district. Can change most rules.
The Intensity Spectrum
← scroll to see all districts →
RSD
Detached
RSA
Row house
RM-1
Low multi
RM-2/3
Mid-rise res
CMX-1
Corner store
CMX-2
Corridor
CMX-2.5
Denser corr.
CMX-3
Mid-rise
CMX-4
High-rise
CMX-5
Center City
IRMX
Ind/res mix
I-1/I-2
Industrial

Relative intensity — height, density, and use mix increase with bar height

Residential Districts

Residential districts are primarily for housing, with commercial uses largely prohibited or requiring a variance. They range from large-lot detached houses (RSD) to dense rowhouse blocks (RSA-5) to mid- and high-rise apartments (RM-2 through RM-4).

Note on RSD districts (RSD-1, RSD-2, RSD-3): These cover detached single-family houses on relatively large lots — think Chestnut Hill, parts of the Northeast, and suburban-style blocks. Minimum lot widths run from 50–75 feet; minimum lot areas from 5,000–10,000 sq ft. Max height is 38 feet. You'll rarely see these in development controversy because by-right redevelopment options are limited to single-family homes. They're primarily relevant when a developer seeks a variance to build something more dense.
RSA-5
Most common residential
The quintessential Philadelphia rowhouse district
RSA-5 covers the attached and semi-detached rowhouse fabric that defines most of Philadelphia's residential neighborhoods — South Philly, Fishtown, West Philly, Kensington, and hundreds of blocks in between. It's designed for single-family homes on small lots, and that's essentially all you can build by right. Adding a second unit requires a variance. Commercial uses of any kind require a variance. The district is notably strict: no corner stores, no duplexes, no offices.
Where RSA-5 gets complicated is in the density math. Minimum lot sizes vary by Council District — 960 sq ft in Districts 1, 2, 3, and 7 (Center City, South Philly, parts of the Northeast); 1,440 sq ft in Districts 4–6 and 8–10. This matters for lot-splitting and new-construction projects. Front setback is also "contextual" — new buildings must match the setback of immediately adjacent buildings, preserving streetscape character.
Max Height38 ft
Min Lot Width16 ft
Min Lot Area960–1,440 sf
Max Coverage75% / 80% (corner)
By-right units1 (single-family)
View RSA-5 on Map
RSA-6
Dense / transit-adjacent rowhouses
The most permissive single-family rowhouse district — but also the shortest
RSA-6 applies to Philadelphia's densest older rowhouse blocks — very small lots, very narrow frontages, very little open space. It's designed for the tightest urban fabric, common in parts of North and West Philadelphia. The critical quirk: RSA-6 has a 25-foot default maximum height, which is the lowest of any residential district. Buildings can go higher (up to 35 or 38 feet) only if the lot meets certain size thresholds or the project includes affordability commitments. This low height limit frequently requires variances for new construction that matches the height of neighboring buildings.
Like RSA-5, only single-family homes are permitted by right. Everything else is a variance.
Max Height25 ft (default)
Min Lot Width14 ft
Min Lot Area700 sf
Max Coverage80%
By-right units1 (single-family)
View RSA-6 on Map
RM-1
Low-density multifamily
Where duplexes, triplexes, and small apartment buildings live — by right
RM-1 is the first district in the residential family where multi-family housing is permitted by right. You'll find it scattered through West Philadelphia, parts of North Philly, and along transit corridors — often on blocks that mix rowhouses with older apartment buildings. The district uses a formula-based density cap rather than a simple unit count: roughly one dwelling unit per 1,600 sq ft of lot area for the first portion of the lot, then one unit per 480 sq ft above that threshold. In practice this allows somewhere between 2 and 10 units depending on lot size. No commercial uses are permitted by right; this is a purely residential district despite a density level that often surprises neighbors accustomed to RSA-5 protections.
RM-1 projects are a common flashpoint in Philadelphia ZBA hearings — often because a developer needs a variance to hit a higher unit count than the formula allows, or because a project in an adjacent RSA-5 block requires RM-1-level density via variance.
Max Height38 ft
Min Lot Width16 ft
Max Coverage75% / 80% (corner)
DensityFormula-based (§14-701)
By-right usesResidential only
View RM-1 on Map
RM-2
Mid-rise residential
Garden apartments and mid-rise buildings — no height limit, but setbacks control massing
RM-2 has no fixed height maximum. Instead, it uses a setback formula tied to building height: setbacks from lot lines must equal at least ¾ of the building's height. This creates an effective height limit based on lot depth — a building on a 50-foot-deep lot can only go so tall before it violates the setback on both sides. FAR is capped at 70% of lot area. This district is relatively rare and tends to appear in institutional edges and planned residential developments.
Max FAR70%
Max HeightNo fixed limit
Min Lot Area15,000 sf
View RM-2 on Map
RM-3
Mid-density residential
More mid-rise apartments; FAR-governed density on larger lots
RM-3 steps up to 150% FAR and introduces a 50% lot coverage limit — meaning buildings on wider lots must leave meaningful open space. Still no fixed height ceiling. Like RM-2, this tends to appear in planned residential contexts, near campuses, or in areas that were remapped to allow more housing without allowing commercial uses.
Max FAR150%
Max HeightNo fixed limit
Max Coverage50%
View RM-3 on Map
RM-4
High-density residential
The highest-density purely residential district
RM-4 reaches 350% FAR — the residential equivalent of a significant urban multifamily building — while keeping uses restricted to housing and residential support services. No ground-floor commercial by right. You'll find RM-4 in a handful of areas where the city wanted to enable dense housing without inviting commercial activity.
Max FAR350%
Max HeightNo fixed limit
Max Coverage75% / 80%
View RM-4 on Map
Commercial Mixed-Use Districts (CMX)

The CMX family is where most of Philadelphia's new housing and retail development happens. All CMX districts allow a mix of residential and commercial uses by right — the differences are in height limits, FAR, use intensity, and required building form. The spectrum runs from a neighborhood corner store (CMX-1) to Center City skyscraper (CMX-5).

CMX-1
Neighborhood corner commercial
The corner store district — commercial uses allowed, but tightly constrained to match the neighborhood
CMX-1 typically applies to individual corner lots or small storefronts embedded in residential blocks. It's the softest commercial zone — designed to allow a shop, cafe, or office where it fits naturally into a rowhouse neighborhood without disrupting the surrounding scale. The defining feature: CMX-1 has no independent dimensional standards of its own. Height, setbacks, and lot coverage must match the most restrictive adjacent residential district. A CMX-1 parcel surrounded by RSA-5 blocks is governed by RSA-5 dimensional rules. This makes CMX-1 buildings contextually appropriate almost by definition.
Uses are limited to neighborhood-scale commercial: retail, offices, personal services, and prepared food shops are by right. Sit-down restaurants and take-out restaurants are prohibited or restricted. No bars, no surface parking lots, no drive-throughs. Residential uses depend on what the adjacent district allows.
Max HeightMatches adjacent
Max FARMatches adjacent
Commercial usesNeighborhood-scale only
Ground-floor req.None
View CMX-1 on Map
CMX-2
Neighborhood commercial corridor
The workhorse of Philly's commercial streets — where most neighborhood retail lives
CMX-2 covers the majority of Philadelphia's commercial corridors: South Street, Germantown Avenue, Baltimore Avenue, Passyunk Avenue, and hundreds of similar mixed-use streets. It's the most commonly remapped-to district when a block is being upzoned from residential. Buildings max out at 38 feet (roughly 3–4 stories) and must match the front-of-lot setback of adjacent buildings. The corridor's small-scale character is preserved by the low height limit and contextual setback rule.
Residential density in CMX-2 varies by lot size and Council District — the code caps allowed units at 2–3 for smaller lots in some districts, scaling to roughly one unit per 480 sq ft for larger lots. Most retail, office, restaurant, and personal services uses are by right. No surface parking lots by right.
Max Height38 ft
Max Coverage75% / 80%
Residential densityCouncil District–dependent
Commercial usesMost retail/restaurant/office
View CMX-2 on Map
CMX-2.5
Dense neighborhood corridor
A step up from CMX-2 — taller buildings, mandatory street-wall, and a higher residential density cap
CMX-2.5 is applied to commercial corridors that can accommodate more height and urban form than the typical neighborhood strip. The key distinctions from CMX-2: the height limit increases to 55 feet (roughly 4–5 stories), buildings must have a minimum cornice height of 25 feet, and — most importantly — buildings must be built to the lot line on primary frontages, creating a continuous street wall. This last requirement is what makes CMX-2.5 blocks feel more urban than CMX-2 corridors.
You'll see CMX-2.5 on denser parts of corridors like North Broad Street, East Passyunk, and the Avenue of the Arts fringe. Residential density formula is the same as CMX-2 but the taller buildings allow more floors of apartments above commercial ground floors.
Max Height55 ft
Min Cornice25 ft
Street WallRequired (build to lot line)
Max Coverage75% / 80%
View CMX-2.5 on Map
CMX-3
Community commercial / urban mixed-use — most debated
The district at the center of most Philadelphia development debates — mid-rise, high-FAR, and broad use permissions
CMX-3 is the most consequential zoning district in Philadelphia for housing production. There's no fixed height limit — instead, there's a base FAR of 500%, which on a typical urban lot translates to a 5–8 story building. Residential uses (multi-family, single-room residences, group living) are all by right, as is an extremely broad range of commercial uses including sit-down restaurants, retail, hotels, medical offices, auto repair, and structured parking.
CMX-3 is where Philadelphia's inclusionary zoning bonuses (see Key Terms: Inclusionary Zoning) do the most work. Mixed-income housing bonuses can push FAR to 750% (moderate income) or 1,250% (low income) in applicable areas — a meaningful increase in building mass. The /TOD overlay, when layered on CMX-3, multiplies base FAR by 1.3 and adjusts parking requirements. CMX-3 remapping from CMX-2 or RSA-5 is the single most common and contested category of zoning action at the ZBA and in Council.
Historic note: Designated historic structures in lower-intensity districts (RSA, CMX-1, CMX-2, CMX-2.5) can access CMX-3 use permissions under §14-602(7) without being remapped, if they had prior non-residential use of 2,500+ sq ft. This is a significant adaptive reuse tool for old churches, schools, and industrial buildings.
Base FAR500%
Max HeightNo fixed limit
Max Coverage75% / 80%
ResidentialAll types by right
CommercialBroad — most uses
IZO bonus FARUp to +750%
CMX-4
High-density urban mixed-use
Tower-scale development along major urban corridors
CMX-4 shares CMX-3's 500% base FAR but allows 100% lot coverage (no open space required for non-residential or tall buildings), enabling larger floorplates. You'll find CMX-4 along Market Street west of Broad, parts of North Broad, University City's main corridors, and other locations where the city explicitly wanted to enable significant density. Nearly all uses are by right, including nightclubs, smoking lounges, and structured parking. Height is unconstrained by base zoning. Bonuses (affordable housing, transit, underground parking) can substantially increase FAR further.
Base FAR500%
Max Coverage100% (non-residential)
Max HeightNo fixed limit
Commercial usesNearly all by right
View CMX-4 on Map
CMX-5
Center City high-rise
The skyscraper district — Center City and University City's towers
CMX-5 covers the high-rise core of Center City and parts of University City. Base FAR is 1,200% — ten times CMX-2 and more than twice CMX-3 — with a mapped area in Center City and University City that allows 1,600% FAR with additional bonuses. This is what makes Center City's towers possible. There are no meaningful use restrictions; essentially everything is by right. Height is limited only by engineering, aviation FAA regulations, and the negotiated bonus framework.
The CMX-5 bonus system is the primary mechanism for negotiating public benefits (affordable housing, public plazas, transit improvements) from skyscraper developers in Philadelphia — a form of density bonus negotiation that replaces the impact fees common in other cities.
Base FAR1,200%
Max FAR (bonuses)Up to 1,600%
Max HeightNo zoning limit
Where mappedCenter City / Univ City
View CMX-5 on Map
Industrial & Mixed Industrial Districts

Philadelphia's industrial districts preserve land for manufacturing, logistics, and related uses — and have increasingly become contested ground as developers seek residential and commercial conversions. Understanding the industrial family matters for covering debates about industrial land loss and anti-displacement policy.

IRMX
Industrial-Residential Mixed-Use
The flex district — light industrial and residential can both locate here by right
IRMX is designed for blocks in transition between industrial and residential use. Multi-family housing is by right; so are artisan industrial, warehouse, and light manufacturing uses. This makes IRMX the preferred designation for adaptive reuse of old factory buildings into residential lofts — but also creates tensions when new housing development prices out the remaining industrial users. At 500% FAR and 60-foot max height (72 feet if 50%+ of the ground floor is industrial), it enables substantial development. You'll find IRMX in Fishtown, Northern Liberties, and Kensington's riverfront edges.
Max FAR500%
Max Height60 ft (72 w/ industrial)
ResidentialMulti-family by right
IndustrialLight/artisan by right
View IRMX on Map
I-1 / I-2 / I-3
Pure industrial
Protected industrial land — residential development is prohibited; commercial uses are limited
The I-series districts are pure industrial zones where residential use is prohibited (only caretaker quarters are allowed). I-1 covers light industrial and fabrication; I-2 adds manufacturing and distribution; I-3 allows the heaviest industrial uses including extractive industries. All three have no height limit unless they abut a residential district, where a 60-foot cap applies. These districts are what advocates refer to as "industrial sanctuaries" — the city's tool for keeping manufacturing and logistics employment land off-limits to residential conversion.
Remapping parcels out of I-1 or I-2 into CMX or IRMX is a recurring debate, particularly as former industrial corridors attract residential interest. The city's Industrially Zoned Land (IMA overlay) provides an additional layer of protection in some areas.
Max FAR500%
Max HeightNo limit (60 ft adj. res.)
ResidentialProhibited
CommercialVery limited in I-1; more in I-2
View I-Series on Map
⚠

Overlays change everything

The base district is the starting point, not the ending point. Philadelphia has more than 30 overlay districts that modify what can be built, how tall it can be, what uses are permitted, how much parking is required, and how affordability is calculated. The most consequential overlays for development coverage are:

/TOD (Transit-Oriented Development) — Reduces or eliminates parking minimums and multiplies base FAR by 1.3 on parcels within 500 feet of designated transit stations. A parcel with CMX-2 zoning inside a /TOD zone can behave very differently than one just outside the buffer.

/NCO (Neighborhood Conservation Overlay) — Adds design requirements in historic neighborhood contexts. Superseded entirely if the parcel is also locally historically designated.

/MIN (Mixed Income Neighborhoods) — Applies mandatory inclusionary affordability requirements to developments of 10+ units in covered areas.

Always check what overlays apply before drawing conclusions about what a zoning designation means for a specific parcel.

Sources & Further Reading
Philadelphia Zoning Code, Title 14 (Chapter 14-400 for district regulations; Chapter 14-700 for dimensional standards; Chapter 14-600 for use permissions).
City Quick Guide: PCPC Zoning Quick Guide, September 2022 (PDF) — note this document may not reflect subsequent code amendments.
District-by-district use breakdowns: phillyzoning.com/zoning-guides/ (Anastasio Law).
Interactive parcel lookup: Philadelphia Atlas (atlas.phila.gov) — shows base zoning and overlays for any address.

This page is a reader reference guide, not legal advice. Zoning calculations for specific parcels require consultation with a licensed professional and review of current code text.