Photo: Russ · CC BY 2.0Living in Potomac, MD: what to set up and who to call
Potomac has no town government of its own, so Montgomery County runs its elections and most services, and its children attend Montgomery County Public Schools. Fiber reaches 96% of addresses in Potomac.
I’m new in town
What to set up in Potomac, and who provides it. Tap an answer for the details and where they come from.
Power, water and internet
Who to call to start service at a new address in Potomac.
Power comes from Potomac Electric Power
Potomac Electric Power (Potomac Electric Power Co), an investor-owned utility, serves all of Potomac. Its homes paid an average of 21.7¢ per kWh in 2025, about $182 a month (its average across Maryland, for customers on its standard service). Maryland lets you buy power from another supplier; 5% of Potomac Electric Power’s home customers do, and Potomac Electric Power still delivers it.
Service territory: HIFLD Electric Retail Service Territories (map dated Aug 2023). Prices and customers: EIA-861, 2025.
Water comes from WSSC Water
WSSC Water supplies almost all of Potomac. It draws surface water and serves 1,900,000 people in all.
No health-based violations reported to EPA in the five years to October 2026, like 82% of the 27 systems serving more than 1,000,000 people.
The latest lead result on file, the 90th percentile of homes sampled in Jan 2018–Dec 2020, was 0.0 ppb, below the 15 ppb action level that applied. It’s from 2020: EPA has no newer result for this system. Results below detection are reported as 0, so 0 doesn’t mean no lead at any tap.
The system’s full record: EPA ECHO report
EPA SDWIS via Envirofacts (violations pulled Oct 9, 2026) and ECHO (lead samples, 2026Q3); service area: EPA Community Water System Service Area Boundaries v3.0. Violations are counted by the start of their compliance period. MD0150005.
4 home internet providers serve Potomac
100% of 14,123 addresses can get 100/20 Mbps; 96% can get fiber.
| Provider | Technology | Addresses | Fastest (Mbps) |
|---|---|---|---|
| Xfinity | Cable | 100% | 2,000/250 |
| Verizon | Fiber, Fixed wireless | 99% | 2,300/2,300 |
| T-Mobile | Fixed wireless | 54% | 100/20 |
| AT&T | Fixed wireless | 47% | 25/3 |
FCC National Broadband Map, as of December 2025. Availability as providers report it, not speeds people get.
We don’t have Potomac’s trash rules yet
Pickup rules, the dump and recycling in Potomac.
Where your child goes to school
Public school districts and the school path by grade.
Potomac is in Montgomery County Public Schools.
B+School gradeSee Schools →U.S. Department of Education, NCES Common Core of Data, 2024–25. Enrollment rules and registration are the district’s.
No town hall: the county runs things
Potomac is unincorporated, so Montgomery County is the local government.
Election office: FVAP local election office directory, updated Aug 2025; jurisdictions: EAC EAVS 2024. Registration rules and links: vote.gov, updated Mar 11, 2026.
Potomac spans 2 ZIP codes
ZIP codes where Potomac residents live, with the share of the town in each.
| ZIP | Post office name | Share of Potomac | ZIP’s residents in Potomac |
|---|---|---|---|
| 20854 | Potomac, MD | 80% | 74% |
| 20817 | Bethesda, MD | 20% | 25% |
20859 is P.O. box or single-organization ZIP with no homes.
Census 2020 ZIP Code Tabulation Areas, by census block; post office names: GeoNames (CC BY 4.0). ZIPs created since 2020 are missing.
Getting around, the ER and the library
One line each; the subject pages have the rest.
ER: CMS hospital data. Library: IMLS Public Libraries Survey, FY2024.
Questions about living in Potomac
Who supplies Potomac’s drinking water, and has it had violations?
WSSC Water (EPA ID MD0150005). It reported no health-based violations to EPA in the five years to October 2026; 82% of systems its size had none. Its latest lead 90th percentile was 0.0 ppb (Jan 2018–Dec 2020), against a 15 ppb action level.
Who provides electricity in Potomac?
Potomac Electric Power (Potomac Electric Power Co), an investor-owned utility. Its homes paid about 21.7¢ per kWh in 2025 (EIA).
What internet providers serve Potomac?
Xfinity, Verizon, T-Mobile, AT&T (FCC, as of December 2025).
What ZIP codes are in Potomac?
20854 (80%), 20817 (20%), by share of residents. Census 2020 ZIP Code Tabulation Areas.
What school district is Potomac in?
Montgomery County Public Schools.
How do I register to vote in Potomac?
In Maryland you can register online until 21 days before Election Day, in person up to and including Election Day, or by mail (postmarked 21 days before). Elections here are run by the Montgomery County Board of Elections. Check your registration at voterservices.elections.maryland.gov.
Sources & dates
Every answer above names its source. Here they are with their dates.
- Water: EPA SDWIS (Envirofacts, pulled Oct 9, 2026), ECHO SDWA 2026Q3, EPA CWS Service Area Boundaries v3.0.
- Power: HIFLD Electric Retail Service Territories (map Aug 2023); EIA-861 final 2025.
- Trash: OpenStreetMap, Geofabrik extract of Oct 9, 2026. © OpenStreetMap contributors (ODbL).
- ZIP codes: Census 2020 ZCTA relationship files; GeoNames postal codes (CC BY 4.0).
- Schools: NCES Common Core of Data, 2024–25.
- Registration: vote.gov, updated Mar 11, 2026 (read Oct 10, 2026). Official sites and area codes: Wikidata.
- Election office: FVAP local election office directory (fetched Oct 10, 2026; each record dated), EAC EAVS 2024 jurisdictions; registration and lookup links from vote.gov’s state data, checked Oct 10, 2026.
- Internet: FCC National Broadband Map, as of December 2025.