In response to concerns regarding potential Russian aggression in Europe in light of Russia’s invasion of Ukraine, multiple NATO members in Europe are implementing voluntary military service programs, while others continue to have mandatory military service programs.

According to The BBC, while NATO countries had large conscripted militaries during the Cold War, many NATO members decreased the size of their militaries following the fall of the Soviet Union. However, the outlet noted that rising tension with Russia in the aftermath of its invasion of Ukraine in 2022 has led some NATO members to develop new plans to recruit more troops.

The BBC reported that nine NATO members in Europe currently use military conscription. The nine NATO members include Denmark, Estonia, Finland, Greece, Latvia, Lithuania, Norway, Sweden, and Turkey.

According to The BBC, Turkey, which uses military conscription, has the second-largest military in the NATO alliance. Turkey requires men between the ages of 20 and 41 to complete between six and 12 months of military service. Meanwhile, Norway requires both men and women to serve in the military for roughly one year.

While Croatia does not currently use military conscription, The BBC reported that the NATO member is planning to reimplement military conscription next year. Croatia is expected to require men between the ages of 19 and 29 to complete two months of basic military training.

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According to The BBC, Albania, Czechia, Hungary, Italy, Luxembourg, Montenegro, North Macedonia, Portugal, Slovakia, Slovenia, Spain, and the United Kingdom currently have professional militaries. While Iceland does not have a traditional military force, the country’s Coast Guard does cover some defense responsibilities.

Germany is one of the NATO members moving forward with a new voluntary military service initiative that could eventually lead to military conscription. According to The BBC, Germany recently approved new legislation to require all 18-year-old males to complete a military questionnaire and a medical examination. In the event of a future war, Germany could use the questionnaires and medical exam results to determine potential military conscripts.

The BBC reported that France is planning to pay male and female volunteers to serve for 10 months of paid military training next year. Meanwhile, Belgium recently invited 17-year-old citizens to volunteer for paid military service, and Romania is planning on launching a four-month voluntary military service program next year.

According to The BBC, Bulgaria implemented voluntary military service in 2020 for citizens up to the age of 40 for six months; in 2023, the Netherlands implemented a voluntary military service; and in 2024, Poland established a one-month voluntary basic military training.