Ontario Meter Bases Guide: Hydro One Requirements, Service Upgrades & Approved Meter Sockets
Ontario Meter Bases Guide: Hydro One Requirements, Service Upgrades & Approved Meter Sockets
This guide helps Ontario electricians, builders, property managers, and homeowners understand how to choose a meter base for Hydro One, Toronto Hydro, Hydro Ottawa, Milton Hydro, Alectra, London Hydro, and other local utility territories.
Learn the difference between CSA-approved meter sockets, utility-accepted meter-mounting devices, isolated neutral meter bases, underground service meter bases, combination overhead/underground sockets, and multi-gang metering options.
⚠️ Ontario Meter Base Approval Disclaimer
Meter base acceptance requirements can change without notice and may vary by utility territory, service type, service size, overhead or underground configuration, and installation conditions.
Before purchasing or installing any meter base, always confirm current requirements with your local utility, the Electrical Safety Authority (ESA), and a licensed electrical contractor. This page is for general educational guidance only and is not a substitute for utility approval, ESA inspection, or professional electrical advice.
For current Hydro One requirements, review the Hydro One CSA-Approved Meter-Mounting Devices Guide and the Hydro One Retail Metering Standards Guide.
What Is a Meter Base?
A meter base, also called a meter socket or meter-mounting device, is the enclosure that holds the electrical utility meter. It is the connection point between the utility supply and the customer’s electrical service equipment. In Ontario, choosing the correct meter base is important because the product must match the utility’s requirements, the service size, the type of service entrance, and the installation conditions.
A residential service upgrade, new home build, duplex conversion, triplex project, apartment metering job, or commercial service installation may each require a different type of meter socket. Common considerations include amperage, voltage, jaw configuration, overhead or underground entry, bypass requirements, isolated neutral requirements, and whether the project needs a single meter base or a multi-gang metering centre.
Ontario Meter Base Requirements
In Ontario, a meter base selection normally involves three layers of review: product certification, local utility acceptance, and electrical inspection. A meter socket may be CSA approved, but that does not automatically mean it is acceptable for every Ontario utility or every service configuration.
1. Product Certification
The meter base should be certified or approved by a recognized standards body such as CSA or ULC where applicable.
2. Utility Acceptance
Hydro One, Toronto Hydro, Hydro Ottawa, Milton Hydro, Alectra, London Hydro, and other LDCs may maintain their own metering standards.
3. ESA Inspection
The final installation must comply with the Ontario Electrical Safety Code and pass the required ESA inspection process.
Hydro One Meter Base Requirements
Hydro One publishes CSA-approved meter-mounting device information and a Retail Metering Standards Guide for low-voltage and medium-voltage service configurations. These documents are key references for contractors working in Hydro One territory.
Hydro One territory includes many rural, semi-rural, residential, agricultural, subdivision, cottage, and service upgrade applications across Ontario. Because Hydro One requirements can be revised, contractors should verify the latest documents before ordering a meter base.
Common Hydro One Project Types
Residential Service Upgrades
Often 200A service upgrades where the contractor must confirm the correct socket type, entry type, and neutral requirement.
Underground Services
May require underground-rated meter socket configurations and utility-specific installation details.
Overhead Services
May involve service mast, weatherhead, meter socket location, and utility clearance considerations.
Combination OH/UG
Combination overhead/underground meter bases may be selected when the project requires flexible entry options.
Meter Base Selection Flowchart
Use this simple selection path as an early planning tool. Final selection must still be verified with the local utility and ESA requirements.
Common Meter Base Manufacturers Used in Ontario
Ontario electricians may encounter several meter base manufacturers depending on utility territory, project requirements, supplier availability, and service design. This page is intentionally brand-neutral in the educational sections so users can understand the requirement first and then select the correct product.
| Manufacturer | Common Applications | Selection Notes |
|---|---|---|
| Hydel | Residential service upgrades, underground service, combination OH/UG, multi-gang metering | Hydel meter bases are commonly considered by Ontario contractors for practical service upgrade and grouped metering applications. |
| Eaton | Residential and commercial electrical service equipment | Major electrical manufacturer with meter socket and service equipment options. |
| Microlectric | Canadian utility and contractor metering applications | Recognized meter socket brand in Canadian electrical distribution. |
| Schneider Electric | Residential, commercial, and industrial electrical equipment | Used across a wide range of electrical service equipment categories. |
| ABB / Leviton / Durham Electrical Products | Specialty and utility-related metering applications | Availability and suitability depend on utility territory and project requirements. |
Which Meter Base Do I Need in Ontario?
200A Residential Service Upgrade
A 200 amp service upgrade is one of the most common reasons homeowners and contractors shop for meter bases in Ontario. The correct model depends on whether the service is overhead, underground, or combination OH/UG, and whether isolated neutral is required.
Underground Meter Base
Underground service applications often require specific meter socket construction and entry configuration. Ontario contractors should confirm utility requirements before choosing an underground meter socket.
Combination Overhead / Underground Meter Base
Combination OH/UG meter bases are useful when the project calls for flexible entry options, but the contractor must still confirm that the exact model is acceptable for the utility and service configuration.
Isolated Neutral Meter Base
Isolated neutral requirements are important in many Ontario service configurations. Before purchasing, contractors should confirm whether an isolated neutral meter socket is required by the utility or by the project design.
Multi-Gang Meter Bases
Duplexes, triplexes, apartment buildings, commercial plazas, and multi-tenant buildings may require grouped metering or multi-gang meter centres. These installations require careful coordination with the local utility and ESA.
Popular Hydel Meter Bases Available from MarsLED
MarsLED stocks contractor-focused Hydel meter bases for Ontario service upgrades, underground services, combination OH/UG applications, and multi-gang metering projects. Final suitability must always be confirmed with the local utility and ESA requirements.
Hydel MSC400TW3
200A Underground Isolated NeutralPopular underground meter socket option for Ontario residential service upgrade applications where isolated neutral is required.
View ProductHydel MSC400TW
200A Underground Isolated NeutralContractor-focused 200A underground meter socket option for Ontario service applications.
View ProductHydel E400RO
200A 4 Jaw OH/UGCombination overhead/underground 4-jaw meter socket option for applicable Ontario service configurations.
View ProductHydel EK400RO
200A 4 Jaw Isolated NeutralCombination isolated neutral meter socket option for Ontario contractors requiring OH/UG flexibility where suitable.
View ProductHydel SDC320PW
3 Gang 200A Grouped MeteringThree-gang meter socket option for duplex, triplex, and small multi-unit metering applications where suitable.
View ProductHydel HC44R
4 Gang 400A Main Multi-TenantFour-gang 400A main meter socket with blank compartment on left side for grouped metering applications.
View ProductHydel H44RH
4 Gang Right-Hand Entry 200A Per PositionFour-gang meter socket with 400A main, 200A per position, right-hand entry, and 4-jaw meter positions.
View ProductOntario Meter Base Selection Guide
Not sure which meter base is suitable for your project? Use this quick visual guide to understand the basic selection path for Ontario meter base applications, including service type, single vs. multi-gang metering, isolated neutral requirements, and common Hydel meter base options available from MarsLED.
Meter Bases by Application
| Application | Common Search Intent | MarsLED Product Path |
|---|---|---|
| 200A Residential Service Upgrade | 200 amp meter base Ontario, residential service upgrade meter socket | MSC400TW3, MSC400TW, E400RO, EK400RO |
| Underground Service | underground meter socket Ontario, Hydro One underground meter base | MSC400TW3, MSC400TW |
| Combination OH/UG | combination overhead underground meter base Ontario | E400RO, EK400RO |
| Duplex / Triplex Metering | duplex meter base Ontario, 3 gang meter socket Ontario | SDC320PW |
| Apartment / Multi-Tenant | 4 gang meter socket Ontario, apartment meter base Ontario | HC44R, H44RH |
Ontario Utility Territory Considerations
Ontario has many local distribution companies. Requirements can vary by territory, and the utility serving the project should be confirmed before ordering a meter base.
Hydro One
Important for rural, suburban, cottage, agricultural, and new service projects across large parts of Ontario.
Toronto Hydro
Toronto projects may involve dense urban layouts, specific metering requirements, and local service constraints.
Hydro Ottawa
Ottawa-area projects may require local utility-specific metering specifications and service connection requirements.
Milton Hydro / Alectra / London Hydro
Always verify local Conditions of Service and current metering requirements before selecting a meter base.
Ontario Meter Base FAQ
What meter base does Hydro One require?
Hydro One requirements depend on service size, service type, overhead or underground configuration, and current Hydro One metering standards. Always verify the latest Hydro One documentation before purchasing or installing.
Can I use any CSA-approved meter base in Ontario?
No. CSA approval is important, but the meter base must also be acceptable to the local utility and installed according to code and inspection requirements.
What is a meter-mounting device?
A meter-mounting device is another term used for the meter base or meter socket enclosure that holds the utility meter.
What is an isolated neutral meter base?
An isolated neutral meter base is designed for applications where neutral isolation is required by the service configuration or utility requirements.
Does Hydro One require isolated neutral?
Requirements vary by service configuration. Contractors should confirm isolated neutral requirements with Hydro One or the local utility before ordering.
What meter base do I need for a 200A service upgrade?
The answer depends on utility territory, service entry type, overhead or underground feed, and isolated neutral requirements. Common options include 200A underground and combination OH/UG meter sockets.
What is a 4-jaw meter socket?
A 4-jaw meter socket is a common socket configuration used in many residential meter base applications. Suitability depends on the utility and service type.
What is a multi-gang meter base?
A multi-gang meter base has multiple meter positions and is commonly used for duplexes, triplexes, apartments, and multi-tenant buildings.
What meter base is used for duplexes or triplexes?
Duplex and triplex projects may require grouped metering or multi-gang meter socket solutions. The local utility must confirm the acceptable configuration.
Are Toronto Hydro requirements the same as Hydro One?
No. Toronto Hydro and Hydro One have separate requirements and documentation. Always verify the requirements of the utility serving the property.
Who approves a meter base installation in Ontario?
The product must meet applicable standards, the local utility must accept the metering configuration, and the installation must meet ESA inspection requirements.
Does MarsLED sell Ontario meter bases?
Yes. MarsLED sells electric meter bases for Ontario contractors, including Hydel single-position and multi-gang meter socket options.
Official Ontario Utility & Safety References
Use these official links to verify current meter base, metering, and inspection requirements before installation.
Need Help Choosing a Meter Base?
MarsLED supports Ontario electricians, contractors, builders, and property managers with electric meter bases, service upgrade products, lighting, ventilation, wire, cable, and electrical supplies.
Call: 905-878-9997
Call: 519-893-6666
Call: 1-833-277-6277
Sales@marsled.com