Aberdeen MD ADU Rules 2026: Sept. 14 Hearing, Proposed Fee Exemptions & What Applies Now

Aberdeen is in an active ADU transition, and homeowners should separate the City’s current published code from three ordinances that are still pending. The City of Aberdeen has scheduled a September 14, 2026 public hearing on Ordinance Nos. 26-O-06, 26-O-07 and 26-O-08. Together, the proposals would revise the Development Code for accessory dwelling units, exempt ADUs from certain residential growth-management standards, and exempt ADUs from several water and sewer-related charges. None of those three proposals should be treated as enacted law yet.

1. Quick answer: can you build an ADU in Aberdeen today?

Aberdeen’s current Development Code already contains an accessory dwelling unit definition, ADU rows in its residential dimensional standards, a 500-square-foot minimum floor area for an ADU, and a current off-street parking schedule requiring one space per ADU. At the same time, the City is considering a new three-ordinance package intended to align and clarify local treatment ahead of Maryland’s October 1, 2026 local-law deadline.

If you are not certain that the property is actually inside Aberdeen City limits, use the Maryland ADU Jurisdiction Finder before relying on this guide.

2. What Aberdeen’s current published Development Code says

Aberdeen’s current code already contains several ADU-related provisions. The City defines an ADU as a residential living unit on the same parcel as, and subordinate to, a single-family dwelling, with complete independent living facilities. The definition recognizes detached units, units within accessory structures such as detached garages, and units created within or through expansion/remodeling of the primary dwelling.

The current code also contains:

• 500 sq ft minimum floor area for an accessory dwelling unit.
• One off-street parking space per ADU in the current parking schedule.
• ADU-specific rows for R-1, R-2 and R-3 in the residential lot/yard standards.
• Separate provisions for an older category called a “dwelling, accessory apartment,” including a 50% above-grade living-area limit. Do not assume that older accessory-apartment language is interchangeable with every ADU under the 2026 state framework.

3. Ordinance 26-O-06: the main Aberdeen ADU zoning rewrite

The City’s official public-hearing notice says Ordinance 26-O-06 would revise Chapter 235 of the Aberdeen Development Code to authorize and regulate ADUs on lots with an owner-occupied single-family detached dwelling, consistent with Maryland requirements.

According to the notice, the ordinance addresses:

• ADU definitions;
• permitted locations;
• lot standards;
• setbacks;
• floor-area standards;
• parking;
• accessory-structure standards;
• related zoning-district and Table of Use Regulations amendments.

Those are exactly the issues homeowners care about, but the hearing notice is a summary, not a substitute for final adopted ordinance text. Maryland ADU Guide will not convert that summary into invented setback or size numbers.

4. Ordinance 26-O-07: ADUs and Aberdeen’s growth-management rules

Ordinance 26-O-07 would amend Aberdeen’s Chapter 302 Growth Management rules so ADUs are exempt from residential development adequacy standards, including school-capacity requirements.

This proposal tracks an important part of Maryland Land Use §4-504: a local ADU law must exclude qualifying ADUs from density calculations and measures limiting residential growth that apply to the lot, parcel or tract.

For homeowners, the practical point is simple: Aberdeen is not only revising zoning language. It is also changing the separate growth-management layer that can affect residential development review.

5. Ordinance 26-O-08: the proposed water and sewer fee exemptions

The most financially interesting part of Aberdeen’s September package may be Ordinance 26-O-08.

The City’s public-hearing notice says the proposal would amend Chapter A550 to exempt ADUs from:

• water area connection charges;
• water meter charges;
• sanitary sewer area connection charges.

If adopted, the fee revision could materially change the early utility-cost conversation for some Aberdeen projects. But a fee exemption does not mean utility work itself is free. Trenching, service modifications, plumbing, engineering, meter configuration, restoration and other project costs can remain.

6. Why Aberdeen is acting now: Maryland’s October 1, 2026 deadline

Maryland Land Use §4-504 requires covered local legislative bodies to adopt a local law authorizing accessory dwelling units on or before October 1, 2026. The statewide definition in §4-501 describes a qualifying ADU as a secondary dwelling unit on the same lot as a primary single-family detached dwelling and no greater than 75% of the size of the primary dwelling.

The state framework also addresses issues such as growth-limit treatment, side/rear setback restrictions and additional ADU parking requirements. That is why Aberdeen’s September package spans zoning, growth management and fees rather than only adding one new definition to the code.

See our Maryland ADU October 1 Deadline Guide and Maryland County & City ADU Rules Tracker for the statewide transition.

7. Current Aberdeen rule vs. September proposal: what can safely be said now?

8. Aberdeen ADU permit path: City permit, County inspections

Aberdeen has an important split in the permitting workflow.

Building permits are applied for through the City of Aberdeen. The City’s Department of Planning and Community Development reviews zoning and permit materials. After a permit is issued, the City says inspections for building, plumbing, electrical and mechanical work are conducted by the Harford County Department of Inspections, Licenses and Permits (DILP).

Aberdeen Public Works separately handles reviews/inspections related to grading, stormwater and public infrastructure, including water meters and water/sewer connection services.

9. What Aberdeen homeowners should do before September 14

1. Confirm the property is actually inside Aberdeen. Use the Jurisdiction Finder.
2. Identify the zoning district. The current code uses district-specific standards, so a citywide setback assumption is unsafe.
3. Do not budget the proposed fee exemptions yet. Treat 26-O-08 as pending until adoption and effective date are verified.
4. Ask the City how it is currently administering ADU parking, floor area and owner occupancy. Those are specifically within the pending zoning revision.
5. If your project is active now, ask whether staff expects submitted plans to be evaluated under current code or an adopted September amendment.
6. Run the property through the Maryland ADU Property Feasibility Checker before spending heavily on design.

10. What to watch at the September 14 hearing

The hearing is scheduled for Monday, September 14, 2026 at 7:00 p.m. at Aberdeen City Hall, Council Chambers, 60 North Parke Street.

The most important homeowner questions after the hearing are:

• Was 26-O-06 adopted, amended, deferred or sent back for further work?
• What final size/setback/parking language was approved?
• Did owner-occupancy language remain in the final zoning ordinance?
• Was the growth-management exemption in 26-O-07 adopted?
• Were all three utility-related fee exemptions in 26-O-08 adopted?
• What are the effective dates?

Maryland ADU Guide will update this same page after the hearing. We will not create a second article simply to repeat the same Aberdeen rules.

11. Bottom line

Aberdeen is one of the Maryland municipalities worth watching closely this week. The current code already contains ADU provisions, but the City has three pending ordinances that could materially affect zoning administration, growth-management review and project costs.

For a homeowner planning now, the safest sequence is: confirm Aberdeen jurisdiction → identify zoning district → verify current administered ADU standards → check utility/site conditions → wait for or account for the September 14 legislative outcome before finalizing assumptions that may change.

Next step: use the Maryland ADU Jurisdiction Finder, then run the Property Feasibility Checker and review the Maryland ADU Rules Tracker.

Primary sources used for this Aberdeen guide

• City of Aberdeen — Public Hearings (26-O-06, 26-O-07, 26-O-08)
• City of Aberdeen — 2026 Legislation Status
• City of Aberdeen Development Code — Definitions
• City of Aberdeen Development Code — Lot, Floor Area, Parking and Accessory Standards
• City of Aberdeen — Building Permit Procedure and Documents
• Maryland Land Use §4-501 — ADU Definition
• Maryland Land Use §4-504 — Local ADU Requirements

Maryland ADU Guide is maintained by Gijo John as an independent research publication. We prioritize enacted code, official legislative records and current government guidance. Proposed legislation is not treated as law. This page is for planning information and is not legal, architectural or permit advice.