Pfäffikon has a population (as of ) of . , 17.6% of the population was made up of foreign nationals. the gender distribution of the population was 49% male and 51% female. Over the last 10 years the population has grown at a rate of 12.1%. Most of the population () speaks German (86.9%), with Italian being second most common ( 4.6%) and Albanian being third ( 2.3%). In the 2007 election the most popular party was the
SVP which received 37.8% of the vote. The next three most popular parties were the
SPS (15.4%), the
CSP (14.5%) and the
Green Party (10.7%). The age distribution of the population () is children and teenagers (0–19 years old) make up 23.5% of the population, while adults (20–64 years old) make up 62% and seniors (over 64 years old) make up 14.5%. In Pfäffikon about 73.3% of the population (between age 25-64) have completed either non-mandatory
upper secondary education or additional higher education (either university or a
Fachhochschule). There are 3954 households in Pfäffikon. 50% of the working population were employed full-time, and 50% were employed part-time. there were 2549
Catholics and 4771
Protestants in Pfäffikon. In the 2000 census, religion was broken down into several smaller categories. From the , 52.5% were some type of Protestant, with 48.6% belonging to the
Swiss Reformed Church and 4% belonging to other Protestant churches. 27.3% of the population were Catholic. Of the rest of the population, 0% were Muslim, 7.5% belonged to another religion (not listed), 2.4% did not give a religion, and 9.5% were atheist or agnostic. ==Weather==