Alftberg was born in Jönköping in 1973 before moving to Borås in the 1980s. He worked for sixteen years as a middle and high school teacher in Borås.[1][2]
In 2018, he was elected as a municipal councilor for the Sweden Democrats in Borås and served as a political secretary to the SD's spokesman on the council. He also sat on the education board within the county.[3] For the 2022 Swedish general election, Alftberg contested the constituency of Västra Götaland County South on the SD's ballot and won a seat. He is expected to take up seat 49 in the Riksdag.[4]
Outside of politics, Alftberg is married with three children. He has cited former British Prime Minister Winston Churchill as a role model.[5]