The Lenzburg district has an area, as of 2009^[update], of 102.71 square kilometers (39.66 sq mi). Of this area, 42.6 km² (16.4 sq mi) or 41.5% is used for agricultural purposes, while 34.14 km² (13.18 sq mi) or 33.2% is forested. Of the rest of the land, 20.16 km² (7.78 sq mi) or 19.6% is settled (buildings or roads).^[2]

The blazon of the district coat of arms is Argent a Hurt.^[3]

Bezirk Lenzburg has a population (as of December 2020^[update]) of 65,707.^[1] As of June 2009^[update], 19.7% of the population are foreign nationals.^[4]

In 2000^[update] there were 24,407 workers who lived in the district. Of these, 18,072 or about 74.0% of the residents worked outside the Lenzburg district while 14,959 people commuted into the district for work. There were a total of 21,294 jobs (of at least 6 hours per week) in the district.^[5]

From the 2000 census^[update], 12,952 or 27.9% were Roman Catholic, while 23,937 or 51.6% belonged to the Swiss Reformed Church. Of the rest of the population, there were 45 individuals (or about 0.10% of the population) who belonged to the Christian Catholic faith.^[2]

Of the school age population (in the 2008/2009 school year^[update]), there are 3,695 students attending primary school, there are 1,569 students attending secondary school, there are 971 students attending tertiary or university level schooling, and there are 12 students who are seeking a job after school in the municipality.^[2]

The district contains a total of 20 municipalities:

47°23′N 8°10′E / 47.383°N 8.167°E / 47.383; 8.167