Therwil (Swiss German: Därwyl) is a municipality in the district of Arlesheim in the canton of Basel-Country in Switzerland.

Therwil is located about 8 kilometres south of the city centre of Basel, to which it is connected by a contiguously built-up area, covered by the municipalities of Oberwil, BL, Bottmingen and Binningen.

Therwil has an area, as of 2009[update], of 7.63 square kilometers (2.95 sq mi).

[3] The blazon of the municipal coat of arms is Or, a Quarter sinistre Sable.

[7] Most of the population (as of 2000[update]) speaks German (7,640 or 90.6%), with English being second most common (169 or 2.0%) and Italian language being third (164 or 1.9%).

The total Swiss population change in 2008 (from all sources, including moves across municipal borders) was an increase of 20 and the non-Swiss population change was an increase of 80 people.

[6] The age distribution, as of 2010[update], in Therwil is; 592 children or 6.2% of the population are between 0 and 6 years old and 1,441 teenagers or 15.0% are between 7 and 19.

[7] The historical population is given in the following chart:[12] In the 2007 federal election the most popular party was the SVP which received 26.11% of the vote.

In the federal election, a total of 3,247 votes were cast, and the voter turnout was 49.4%.

[7] There were 4,354 residents of the municipality who were employed in some capacity, of which females made up 44.0% of the workforce.

The number of jobs in the secondary sector was 762, of which 655 or (86.0%) were in manufacturing and 95 (12.5%) were in construction.

In the tertiary sector; 210 or 20.3% were in wholesale or retail sales or the repair of motor vehicles, 75 or 7.3% were in the movement and storage of goods, 61 or 5.9% were in a hotel or restaurant, 47 or 4.6% were in the information industry, 43 or 4.2% were the insurance or financial industry, 122 or 11.8% were technical professionals or scientists, 138 or 13.4% were in education and 206 or 20.0% were in health care.

[7] From the 2000 census[update], 3,219 or 38.2% were Roman Catholic, while 3,046 or 36.1% belonged to the Swiss Reformed Church.

[15] The BBC reported that in April 2016 Therwil became "the centre of a national debate about Swiss identity" after it exempted two Muslim students from greeting their professors with a handshake, as it is otherwise customary in Therwil for all other students.

[16] USA Today further reported that one of the students has "posted material on his Facebook page in support of the Islamic State".