Erlinsbach is a municipality in the district of Aarau of the canton of Aargau in Switzerland.

[3] During the Middle Ages the hamlets of Obererlinsbach and Niedererlinsbach were part of Erlinsbach.

In the 14th century, the hamlet of Edliswil was abandoned, however its exact location is currently unknown.

Of the rest of the land, 10.6% is settled (buildings or roads) and the remainder (0.9%) is non-productive (rivers or lakes).

[4] The municipality is located in the Aarau district between the Aare river and Jura Mountains on the border with the Canton of Solothurn.

It is near the Salhöhe Pass, a regionally important route over the Jura Mountains.

[4] The age distribution, as of 2008[update], in Erlinsbach is; 359 children or 10.3% of the population are between 0 and 9 years old and 384 teenagers or 11.0% are between 10 and 19.

[11] From the 2000 census[update], 957 or 29.1% are Roman Catholic, while 1,593 or 48.5% belonged to the Swiss Reformed Church.