For the purposes of this code, the City is hereby divided into districts as follows:

one class of mixed use district: S (squares and streets)

two classes of residential districts: R (general); H (apartment)

two classes of business districts: L (local); B (general)

three classes of industrial districts: M (restricted manufacturing); I (general); MER (maritime economy reserve)

one class of open space district: OS (open space)

downtown districts (established pursuant to Section 3-1C (Neighborhood District)), as listed in Subsection (f) of this Section;

neighborhood districts (established pursuant to Section 3-1B (Downtown District), as listed in Subsection (g) of this Section;

the Harborpark District (established pursuant to Section 3-1D), as listed in Subsection (h) of this Section; and

special districts (established pursuant to Section 3-1E), as listed in Subsection (i) of this Section.

Land in private ownership shall not be included in the open space class of district without the written consent of the owner.

Each of the residential, business, and industrial classes is further subdivided into subdistricts, which are identified by a number specifying the maximum allowed floor area ratio and some of which have a second number specifying a height limit. The open space district may be divided into open space subdistricts in accordance with the provisions of Article 33. Mixed Use Districts, downtown districts, neighborhood districts, special districts, and the Harborpark District are divided into variously titled subdistricts and subareas, as set forth in the applicable articles of this code.

(a)

Mixed Use Districts: S0, S1, S2, S3, S4, S5

(b)

Residential Districts: R-.8 General, H-1-50, H-1, H-2-65, H-2 Apartment, H-3-65, H-3, H-4, H-5

(c)

Business Districts: L-.5, L-1, L-2-65, L-2, B-1, B-2, B-3-65, B-4, B-6-90a General, B-6-90b, B-8-120a, B-8-120b, B-8-120c, B-8, B-10

(d)

Industrial Districts: M-1, M-2 Restricted Manufacturing, M-4, M-8, I-2 General Industrial, MER-2, Maritime Economy Reserve

(e)

Open Space Districts: OS (Open Space), OS-A (Air-Right), OS-CM (Cemetery), OS-G (Community Garden), OS-P (Parkland), OS-RC (Recreation), OS-SL (Shoreland), OS-S (Stadium), OS-UP (Urban Plaza), OS-UW (Urban Wild), OS-WA (Waterfront Access Area)

(f)

Downtown Districts

(g)

Neighborhood Districts

(h)

Harborpark District

(i)

Special District

Central Artery Special District

The boundaries of the above districts are established as shown on a series of maps entitled "Zoning Districts City of Boston," dated August 15, 1962, on file in the office of the City Clerk, which maps, with all explanatory matter thereon, and all maps which, by amendment of this code, may be substituted therefor or made supplemental thereto shall be deemed to be, and are hereby made, a part of this code.

The locations of open space districts shall be identified and designated by map or text amendment of this code. Notwithstanding that the site of a designated open space district appears to be in a residential, business, industrial, or other district on any map in the series of maps entitled "Zoning Districts City of Boston," such site is in an open space district.

(Text Amd. No. 471, §§ 2, 14i., 14j., 4-23-2024; Text Amd. No. 475, § 1, 5-30-2024; Text Amd. No. 491, 10-28-2025)

A subdistrict or part thereof or a contiguous group of subdistricts or parts thereof may be designated as a special purpose overlay district as follows:

(a)

planned development area (distinguished by the addition of the letter "D" to the designation of the subdistrict or subdistricts);

(b)

urban renewal area (distinguished by the addition of the letter "U" to the designation of the subdistrict or subdistricts);

(c)

restricted and limited parking districts;

(d)

adult entertainment district (distinguished by the addition of the letter "E" to the designation of the subdistrict or subdistricts);

(e)

flood hazard district;

(f)

institutional district;

(g)

restricted roof structure district (distinguished by the addition of an asterisk to the designation of the subdistrict or subdistricts);

(h)

interim planning overlay district;

(i)

limited height district (distinguished by the addition of a second numerical suffix added to the basic district designation);

(j)

greenbelt protection overlay district;

(k)

density limitation district;

(l)

groundwater conservation overlay district;

(m)

smart growth overlay district. Other special purpose overlay districts may be designated in downtown districts, neighborhood districts, and the Harborpark District, as provided in the articles governing such districts. In an overlay district the regulations specified for the base subdistrict or subdistricts shall apply, insofar as they are not in conflict with special regulations specified for a particular overlay district;

(n)

urban agriculture overlay district;

(o)

greenway overlay district;

(p)

resilience overlay district

a.

Planned Development Areas. The whole or any part of a subdistrict may be established as a planned development area if such area contains not less than one acre and the commission has received from the Boston Redevelopment Authority, and has approved, a development plan or, if the area contains not less than five acres and is not located in a residential zoning district, a master plan for the development of the planned development area. Before transmittal to the commission, such development plan or master plan shall have been approved by said Authority after a public hearing, provided, however, that no development plan or master plan shall be approved by said Authority unless said Authority finds that such plan conforms to the general plan for the city as a whole and that nothing in such plan will be injurious to the neighborhood or otherwise detrimental to the public welfare. A development plan shall set forth the proposed location and appearance of structures, open spaces and landscaping, proposed uses of the area, densities, proposed traffic circulation, parking and loading facilities, access to public transportation, proposed dimensions of structures, and may include proposed building elevations, schematic layout drawings and exterior building materials, and such other matters as said Authority deems appropriate to its consideration of the proposed development of the area. ^{1 [2]}

If the area contains not less than 5 acres and is not located in a residential zoning district, a master plan may be submitted setting forth only a statement of the development concept, including the planning objectives and character of the development, the proposed uses of the area, the range of dimensional requirements contemplated for each of the proposed uses, the proposed phasing of construction of the development and such of the other items set forth above as said Authority may request in order to make its required finding. No work shall proceed in any planned development area established by the commission on the basis of an approved master plan until a development plan for the area, or portion thereof in which work is to proceed, conforming to the foregoing requirements has been approved by the Authority and the commission, in each case after a public hearing.

To insure that no work proceeds other than in accordance with an approved development plan, no structure shall be erected, reconstructed, or structurally changed or extended in a planned development area, whether or not a master plan has been approved for such area, unless all drawings and specifications therefor shall have been subjected to design review and approved by said Authority. The Building Commissioner shall not issue any building or use permit with respect to any building, structure, or land within a planned development area unless the Director of said Authority has certified on the application therefor and on each and every plan filed with the Building Commissioner in connection therewith that the same is consistent with the development plan for such planned development area or the portion thereof to which said permit relates. Except as otherwise provided in Article 6A or Article 80, planned development areas shall be subject to all the provisions of this code applicable to the subdistrict in which the area is located.

b.

Urban Renewal Areas. Upon application from the Boston Redevelopment Authority, the whole or any part of a subdistrict may be established as an urban renewal area if all land within such urban renewal area is the site of or for a low rent housing project, or a housing project for elderly persons of low income, or consists solely of land, including land under water, with respect to which an agreement has been entered into with said Authority establishing use and dimensional controls as specified in a land assembly and redevelopment, or urban renewal plan, as defined in Chapter 121 of the General Laws. Articles 8, 13, 14, 15, 16,17,18, 19, 20, 21,22, 23, 24, and the provisions of this code establishing use, dimensional, parking, and loading requirements for any Neighborhood District established under Section 3-1B (Downtown District) or for any Downtown District established under Section 3-1C (Neighborhood District) or for any Harborpark District established under Section 3-1D shall not apply to urban renewal areas; but except as otherwise provided in Article 6A, urban renewal areas shall be subject to all other provisions of this code applicable to the subdistrict in which the area is located.

c.

Restricted and Limited Parking Districts. In a restricted parking district, off-street parking facilities, including parking lots, parking garages, and parking accessory or ancillary to any use other than Use Items numbered 1 through 15, shall be conditional uses which may be granted only in conformance with the provisions of Section 6-3A as well as Sections 6-2, 6-3 and 6-4.

In a limited parking district, Use Item Nos. 58 and 59, parking lot and parking garage, shall be forbidden uses. (Note: These restrictions are not applicable to land of agencies or authorities of the Commonwealth of Massachusetts or the United States of America that are not subject to municipal zoning.)

d.

Adult Entertainment District. An adult entertainment district is an overlay district in which Use Items No. 34A and 38A (adult books and adult entertainment) are allowed, and in which the prohibition of moving or flashing signs in Section 11-2 does not apply.

e.

Flood Hazard Districts. The location of and regulations for flood hazard districts are set forth in Article 25 of this code.

f.

Institutional District. Notwithstanding the provisions of Table B of Section 8-3 (Use Regulations), in an institutional district the following uses are conditional uses in instances where they would otherwise be allowed under said Table B: any use listed under Use Item No. 16, 17, 20, 22A, 28, 29, or 30. Use Item No. 72, accessory parking, shall be a conditional use if the main use to which it is accessory is in existence at the time that new or additional parking spaces are applied for and if such main use is a use listed under Use Item No. 11, 12, 13, 13A, 14, 16, 16A, 17, 18, 19, 20, 22A, 28, 29, or 30.

g.

Restricted Roof Structure Districts. All or part of a subdistrict that is characterized by groups of buildings with identical or similar heights within such groups may be designated as a restricted roof structure district, the regulations for which are set forth in Section 16-8.

h.

Interim Planning Overlay District. A district or group of districts or a subdistrict or group of subdistricts or parts thereof (hereafter referred to as an area) may be established as an interim planning overlay district when it is determined by the Zoning Commission that:

(1)

the existing zoning is thought to be inappropriate;

(2)

a rezoning of the area is anticipated;

(3)

a comprehensive planning study preceding the anticipated rezoning is needed; and

(4)

interim land use regulations are essential to maintain the status quo in the area and prevent introduction of changes to the area which may be incompatible with the goals of the comprehensive planning study or anticipated rezoning. The regulations governing the interim planning overlay district are set forth in Article 27.

i.

Limited Height Districts. A limited height district may be established by map amendment which adds to the basic subdistrict designation or designations a numerical suffix indicating the maximum height in feet for buildings in such district. When such limited height district designation does not appear in the first column of Table B of Section 13-1, the dimensional requirements of such district shall be as specified in said Table B for the base district, except that the maximum height of buildings shall be as specified by such suffix.

j.

Greenbelt Protection Overlay District. An area along a Greenbelt Roadway may be established as a Greenbelt Protection Overlay District when the Zoning Commission determines that this designation is necessary to promote the purposes stated in Section 29-1. The requirements and regulations for Greenbelt Protection Overlay Districts are set forth in Article 29.

k.

Density Limitation District. All or part of a subdistrict that is characterized by groups of residential buildings with similar heights within such groups may be designated as a density limitation district, the regulations for which are set forth in Use Items No. 8 and No. 8A of Table B in Section 8-3 (Use Regulations). For purposes of this section, usable interior living area is the area of a dwelling unit in a structure as measured by the interior faces of the walls of the unit, but excluding therefrom areas excluded from gross floor area as defined by Section 2-1, "Floor area, gross," but also excluding any open space or open or enclosed porches, balconies or decks.

l.

Groundwater Conservation Overlay District. All or part of a district where structures supported on wood pile foundations are known or thought to be known may be established as a Groundwater Conservation Overlay District, the regulations of which are set forth in Article 32.

m.

Smart Growth Overlay District. The whole or part of one or more districts or subdistricts may be established as a Smart Growth Overlay District if such area is in a Downtown District and contains not less than one-half acre of land or air rights or if such area is in a Neighborhood District and contains not less than one acre of land or air rights and if a planning study has been done to determine that the area is an appropriate area to encourage smart growth and increased housing production. The further requirements for adopting a Smart Growth Overlay District are set forth in Article 87.

n.

Urban Agriculture Overlay District. All or portions of the Greater Mattapan Neighborhood District may be established as an Urban Agriculture Overlay District when the Zoning Commission determines that this designation is necessary and appropriate for the reasons stated in Section 60-28. No other Districts or subdistricts in the City are permitted to adopt this overlay district.

o.

Greenway Overlay District.

p.

Resilience Overlay District. All or part of one or more subdistricts may be established as a Resilience Overlay District when the Zoning Commission determines that this designation is necessary and appropriate to advance the City's goal of protecting persons and structures from adverse impacts of climate change through resilient planning and design. The Zoning Commission may designate different types of Resilience Overlay District to address specific impacts and responses. These may include, but are not limited to coastal flooding, stormwater flooding, urban heat islands, and urban forest protection. The requirements and regulations for Coastal Flood Resilience overlay districts are set forth in Article 25A.

(Text Amd. No. 471, §§ 2, 14g., 14i., 14j., 4-3-2024; Text Amd. No. 488, § 2, 10-28-2025)

A district or group of districts or a subdistrict or group of subdistricts or parts thereof (hereafter referred to as an area) may be designated a downtown district after a planning study of the area has been conducted. The regulations governing any such downtown district are set forth in Articles 38, 39, 40, 41, 43, 44, 45, 46, and 47A. The boundaries of any such downtown district are shown on the "Zoning Districts City of Boston" maps, as amended, or supplements thereto. Downtown districts are listed in Section 3-1(f). The provisions of this code establishing use, dimensional, parking, and loading requirements for the downtown districts shall not apply to urban renewal areas established under Section 3-1A.b

(Text Amd. No. 471, § 2, 4-3-2024)

A district or group of districts or a subdistrict or group of subdistricts or parts thereof (hereafter referred to as an area) may be designated as a neighborhood district after a planning study of the area has been conducted. The regulations governing any such neighborhood district are set forth in an article of this code pertaining to such district. The boundaries of any such neighborhood district are shown on the "Zoning Districts City of Boston" maps, as amended, or supplements thereto. A subdistrict or subdistricts within a neighborhood district may be distinguished on such maps or supplements by the addition of the letter "N" to the designation of such subdistrict or subdistricts. The provisions of this Code establishing use, dimensional, parking, and loading requirements for the neighborhood districts shall not apply to urban renewal areas established under Section 3-1A.b. of this Code.

(Text Amd. No. 471, § 2, 4-3-2024)

The Harborpark District is established pursuant to the provisions of Article 42A, 42B, 42C, 42D, 42E, and 42F. The provisions of this code establishing use, dimensional, parking, and loading requirements for the Harborpark District shall not apply to urban renewal areas established under Section 3-1A.b.

(Text Amd. No. 471, § 2, 4-3-2024)

A district or group of districts or a subdistrict or group of subdistricts or parts thereof (hereafter referred to as an area) may be designated a special district after a planning study of the area has been conducted. The regulations governing any such special district are set forth in an article of this code pertaining to such district. The boundaries of any such special district are shown on the "Zoning Districts City of Boston" maps, as amended, or supplements thereto. Special districts are listed in Section 3-1(i).

(Text Amd. No. 471, § 2, 4-3-2024)

Where a district boundary is indicated on a map constituting part of this code as approximately following, or parallel to, the center line or side line of a street, highway, railroad right-of-way, or water course, such boundary shall be construed as following, or as being parallel to, such center line or side line. Where a district boundary is indicated on such a map as approximately following a lot line, such line shall be construed to be said boundary. If no distance is indicated on such a map for a district boundary running parallel to the center line or side line of a street or highway, such dimension shall be assumed to be one hundred feet from such line or, if as determined by the use of the scale shown on such map it is at least twenty feet more, or twenty feet less, than one hundred feet, it shall be as so sealed.

(Text Amd. No. 471, § 2, 4-3-2024)