Ethnikos Piraeus Water Polo Club is the professional water polo team of Ethnikos OFPF (meaning: National Club of Fans of Piraeus and Phalerum, in Greek: Εθνικός Όμιλος Φιλάθλων Πειραιώς Φαλήρου).
The Greece men's national water polo team for many years consisted of Ethnikos players that have participated in the Olympics.
Other great players that have played for Ethnikos are Ioannis Garifallos, Giannis Karalogos, Thomas Karalogos, Nondas Samartzidis, Kyriakos Iosifidis, Markellos Sitarenios, Sotirios Stathakis, Evangelos Patras, Konstantinos Kokkinakis, Filippos Kaiafas, Theodoros Kalakonas, Dimitrios Mazis, Christos Afroudakis, Antonios Aronis, Dimitrios Konstas, Dimitrios Kougevetopoulos, Antonios Vlontakis, Gerasimos Voltirakis, Anastasios Schizas, Chris Humbert, Wolf Wigo, Ashleigh Johnson, Iefke van Belkum, Stephania Haralabidis, Ioanna Haralabidis, Maria Tsouri, Aikaterini Oikonomopoulou, Sofia Iosifidou, Marina Canetti Ethnikos dominated in Greek Water Polo championship for decades.
In 1980, Ethnikos became the first Greek team to reach the Final-4 of LEN Champions League (the elite European club competition).
On July 31, 1927 Ethnikos was defeated in the final by Olympiakos 3–2 in a match that he appealed for a late goal scored by its opponent which led to extra time.
After days and meetings of the sports department of SEGAS with representatives of the two teams, a rematch is set to take place on the 16th of August.
The first championship after the establishment of KOE (National Swimming Federation) came in 1931 with Ethnikos conquering it again undefeated by defeating the then three-time consecutive champion Aris Thessaloniki in the final with 1–0.
In the following season, Ethnikos started his dynasty and won the championship undefeated for the first time after 5 years, achieving 4 wins and 1 draw in 5 games (3–3 with P. Faliro, victory over Mytilini, 10–1 victory over Achilleas Patras, 10–3 over Aris and 5–1 over Olympiakos on 18/9/1953 in front of an audience of 5,000 spectators at the Zappeion Olympic swimming pool).
From 1953 to 1963, the blue and whites of Piraeus won 11 consecutive undefeated championships, a record that has not happened in any other sport.
During the 1950s, he began a long unbeaten streak in league games, which lasted 13 years, a record that remains to this day.
The 115 consecutive unbeaten domestic matches (including Central Championship and Greek Cup matches) were: This group consisted of Andreas Garifallos, Petros Kalfamanolis, Mimi Georgiadis, Yiannis Thymaras, Manolis Patlakas, Dimitris Kourantis, Nikos Lekakis, Kalomiris, Andreadis, Petros Chatzikyriakakis, Panagiotis Chatzikyriakakis, Panagiotis Takousis.
In 1971, the team would lose the title for the first time since 1952 due to a loss to Olympiakos in the second play-off match (2–1).
1987–88 saw the last undefeated championship with Ethnikos dominating Glyfada to take first place in regular time and thus home advantage in the finals.
In 1989–90 Ethnikos will have problems in the regular season and despite the fact that he finishes second as in 1987, it has already lost three times (to Glyfada, Chios and Olympiakos).
There, Ethnikos leads 6–4 but Olympiacos reacted and sent the final to overtime while having two shots at the post three seconds before the end of the match (8–8 regular time).
In 1995–96 he finished fourth in the regular season and was eliminated by Vouliagmeni in the semi-finals of the league but remained unbeaten against their "eternal" rival and eventual champion Olympiakos, winning 9–8 (10/4/1996) and drawing 10–10 (2/12/1995).
In the 1996–97 and 1997–98 seasons, Ethnikos will face internal administrative and financial problems with the team having their worst years up to that point.
Patras, Kaifas, Moustakarias have left and the team now relies on Kalakonas, Kourtidis, while it is also necessary to develop the young Kokkinakis, Schizas, Stellatos, Blanis.
Nevertheless, in 1997 he managed to make it very difficult for the later champion Vouliagmeni, losing in the first stage of the playoffs with 2–1 victories, while his one defeat came in overtime.
In 2002–03 coached by Dragan Matutinović, Ethnikos men's team competed in the semi-finals of the LEN Trophy, but were knocked out by eventual cup winners Brescia and finished third together with Italian side Savona.
A landmark of the year was the resounding transfer of Vlontakis, one of the best strikers in the world at the time, from the European champion, Olympiakos, as well as Makis Voltyrakis, who had just retired.
In 2003–04 with Voltyrakis now as coach, Ethnikos would finish fifth, disappointing the ambitions that had been created to contest for the championship against Olympiakos and Vouliagmeni.
Earlier that year Ethnikos had won the 12th Greek Cup by defeating NO Patras in the final of Thessaloniki.
In 2005–06, although Ethnikos drew once and lost once to Olympiakos in the regular season meetings to finish second in the regular season, meaning Ethnikos had home court disadvantage in the finals, they managed to win the 38th championship in the last fifth game decided in overtime by a score of 7–6.
They repatriated with a huge price Christos Afroudakis who played in Pozilipo Napoli, brings to Piraeus the goalkeeper of the national team of Serbia, Denis Sefik, while Thodoris Kalakonas, a child who grew up in the club (1990–2001, his first tenure) returned from Panionios.
In 2008–09 the team, after administrative turmoil and the departure of funder George Vasilopoulos as well as of several players (Vlontakis, Mazis, Mylonakis, Karabetsos) some of whom had grown up in the club (Kokkinakis, Blanis, Stellatos), had a bad year and was relegated to A2 for first time since 1928.
The following season 2012–13, despite the fact that the team was on the verge of extinction and with the main goal of staying in A2, it will be unexpectedly promoted thanks to the management of president Antonis Printezis and the financing of Alexandros Karydopoulos and will play again in A1 in 2013–14 where Ethnikos would be ranked.
In 2014–15 they had a great regular season and finished second for the first time since 2008, but in the semi-finals of the league playoffs they will be eliminated by PAO and miss out on playing Olympiakos in the finals.
In 2021–22 and 2022–23 it finished seventh out of sixteen teams with one of the lowest budgets in the division while also reaching the final four of the cup in 2023.
Ethnikos Piraeus took part in the Tom Hoad Cup at the Melville Water Polo Club, Fremantle, Australia.