 1,863 (or about 17.86% of the population) belonged to no church, are agnostic or atheist, and 424 individuals (or about 4.07% of the population) did not answer the question.In Birsfelden about 4,379 or (42.0%) of the population have completed non-mandatory upper secondary education, and 1,058 or (10.1%) have completed additional higher education (either university or a "Fachhochschule").Of the 1,058 who completed tertiary schooling, 57.6% were Swiss men, 23.6% were Swiss women, 11.7% were non-Swiss men and 7.1% were non-Swiss women.