Greek Utility Operators: DEDDIE, EYDAP, EYATH and Beyond

Greece has several utility operators responsible for power, water, and telecommunications infrastructure. Knowing which operator serves your area — and how to reach them — is the first step when an outage occurs. This guide explains each operator, their coverage, and what to do when their service fails.

Power Distribution: DEDDIE / HEDNO

DEDDIE (Διαχειριστής Ελληνικού Δικτύου Διανομής Ηλεκτρικής Ενέργειας) — also known internationally as HEDNO (Hellenic Electricity Distribution Network Operator) — is responsible for the low-voltage and medium-voltage power distribution network across all of Greece, including the islands. DEDDIE does not generate or sell electricity; it maintains the physical cables, poles, and substations that deliver power to homes and businesses. When you experience a power outage, it is almost always DEDDIE's network that is affected — regardless of which electricity supplier (retailer) you pay your bill to.

Water in Athens: EYDAP

EYDAP (Εταιρεία Ύδρευσης και Αποχέτευσης Πρωτευούσης) is the water utility for the Athens and Attica region, serving approximately 4 million people. EYDAP operates the reservoirs, treatment plants, and pipe network that supply drinking water across the capital. Water outages in Attica are typically caused by pipe breaks, valve maintenance, or planned network upgrades. EYDAP provides advance notice for scheduled interruptions via their website and local announcements.

Water in Thessaloniki: EYATH

EYATH (Εταιρεία Ύδρευσης και Αποχέτευσης Θεσσαλονίκης) serves Thessaloniki and the surrounding Thessaloniki regional unit. It operates independently from EYDAP with its own infrastructure and fault-reporting system.

Water Everywhere Else: DEYA

Outside Athens and Thessaloniki, water supply is managed by local DEYA (Δημοτική Επιχείρηση Ύδρευσης Αποχέτευσης) utilities — one per municipality. Each DEYA operates independently. To find your local DEYA's fault line, search for "ΔΕΥΑ [your municipality name]" or contact your municipal offices.

Internet and Telecommunications

Broadband internet in Greece is provided by private ISPs — not government-owned utilities. The main providers are: - Cosmote (OTE Group): the largest fixed-line and mobile provider in Greece - Vodafone Greece: second-largest, offers VDSL, fiber, and mobile - Nova: formerly Wind and HOL, offers cable and fiber - DIGI: fiber-focused provider expanding in major cities Each ISP operates its own network infrastructure. A fault at the backbone level can affect thousands of customers simultaneously — this is when the Outage.gr internet outage reports cluster on the map.

Why Knowing Your Operator Matters

When you report an outage on Outage.gr, selecting the correct provider (if known) contributes to the provider accountability rankings. Over time, this data reveals which operators have the most frequent outages and the longest restoration times — publicly, transparently, and based on community experience rather than corporate press releases.