Seengen is a municipality in the district of Lenzburg in the canton of Aargau in Switzerland.

Seengen lies in the Seetal valley to the north of Lake Hallwil.

The municipality has an area, as of 2009[update], of 9.69 square kilometers (3.74 sq mi).

[3] The blazon of the municipal coat of arms is Argent an Eagle displayed Sable beaked, langued and membered Gules.

[7] The age distribution, as of 2008[update], in Seengen is; 382 children or 11.7% of the population are between 0 and 9 years old and 435 teenagers or 13.3% are between 10 and 19.

[7] In the 2007 federal election the most popular party was the SVP which received 38.8% of the vote.

[7] The historical population is given in the following table:[8] It is home to one or more prehistoric pile-dwelling (or stilt house) settlements that are part of the Prehistoric Pile dwellings around the Alps UNESCO World Heritage Site.

[7] From the 2000 census[update], 500 or 19.8% were Roman Catholic, while 1,578 or 62.5% belonged to the Swiss Reformed Church.

It was open a total of 250 days with average of 11 hours per week during that year.