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Supply authority (electrical)

An electrical supply authority is the distribution network owner-operator on the supply side of the meter. State-by-state DNSP list and connection process for builders.

By Chalkline. Last updated 14 May 2026. Verified 14 May 2026.

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A supply authority is the electrical distribution network owner-operator responsible for everything on the supply side of the meter: the poles, the wires from the substation to the property boundary, the service cable to the meter box, and the meter itself in many cases. The technical name is Distribution Network Service Provider (DNSP). The customer-installation side of the meter (every circuit in the house) is the licensed electrician’s responsibility under AS/NZS 3000.

State-by-state DNSPs:

  • NSW: Ausgrid (Sydney metro), Endeavour Energy (Sydney west / Blue Mountains / Illawarra), Essential Energy (regional NSW).
  • VIC: AusNet Services (east), CitiPower (CBD), Powercor (west), Jemena (north-west Melbourne), United Energy (south-east).
  • QLD: Energex (south-east), Ergon Energy (regional).
  • WA: Western Power (south-west grid), Horizon Power (regional and remote).
  • SA: SA Power Networks.
  • TAS: TasNetworks.
  • NT: Power and Water Corporation.
  • ACT: Evoenergy.

What the supply authority does on a residential build:

  • Confirms service capacity (single phase vs three phase) and the supply route (overhead vs underground).
  • Issues the connection application approval (commonly via the electrician’s portal).
  • Installs or upgrades the service main to the boundary.
  • Owns and maintains the point of attachment (the consumer mains termination), the service line, and the meter.
  • Energises the installation when the licensed electrician submits a Certificate of Compliance Electrical Work (or state equivalent) and notice of installation work.

The customer side stops at the main switch (or in some networks the load side of the meter). Anything past the meter is licensed-electrician work.

Service and Installation Rules. Every DNSP publishes its own Service and Installation Rules (sometimes called Customer Connection Service Rules, or similar). The Rules are the binding technical specification for how the service connection is made, where the meter is sited, what consumer mains size is required, and what notifications the electrician must lodge. Builders should treat the local DNSP’s Rules as a compliance document equivalent to a state Act for service-connection purposes.

For builders.

  1. Apply early. New connection applications in metro Sydney and Melbourne can take 6 to 12 weeks just for approval, before any physical work happens. In regional areas, longer.
  2. Confirm the supply on the design. Three-phase requirement for ducted air-con, EV charging, or solar export above 5 kW per phase is the most common scope creep.
  3. The electrician is the touchpoint. Builders rarely deal with the DNSP directly; the licensed electrician submits the connection application, schedules meter install, and books the energisation.

Also known as: DNSP, DNO, network operator, electrical distributor.

Category: Compliance / electrical / utilities.

See also

Last updated: 2026-05-14. Verified: 2026-05-14.

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