Children in the military
About 40% of the Bolivian army was believed to be under the age of 18, with half of those below the age of 16. As of 2018, Bolivia invites children to begin their adult conscription early, from age 17.

Brazil: In Brazil the local organized crime groups, such as Comando Vermelho, recruit children to sell drugs and commit homicides, as well as to fight with the police and other rival groups. Also the Brazilian militias recruit children to fight in the conflict against Comando Vermelho.

Canada: In Canada, people may join the reserve component of the Canadian Forces at age 16 with parental permission, and the regular component at 17 years of age, also with parental permission. They may not volunteer for a tour of duty until reaching age 18.

Colombia: In the Colombian armed conflict, from the mid-1960s to present, one-fourth of non-state combatants have been and still are under 18 years old. In 2004 Colombia ranked fourth in the world for the greatest use of child soldiers. There are currently 11,000–14,000 children in armed groups in the country. In negotiations with the government, armed groups have offered to stop the recruitment of minors as a bargaining chip, but they have not honoured these offers. Bjørkhaug argues that most child soldiers were recruited through some combination of voluntary participation and coercion.
In 1998 a Human Rights Watch press release indicated that 30 percent of some guerrilla units were made up of children and up to 85 percent of some of the militias, which are considered to serve as a "training ground for future guerrilla fighters", had child soldiers In the same press release it was estimated that some of the government-linked paramilitary units consisted of up to 50 percent children, including some as young as eight years old.
In 2005 an estimated 11,000 children were involved with left- or right-wing paramilitaries in Colombia. "Approximately 80 percent of child combatants in Colombia belong to one of the two left-wing guerrilla groups, the FARC or ELN. The remainder fight in paramilitary ranks, predominately the AUC." According to P. W. Singer the FARC attack on the Guatape hydroelectric facility in 1998 involved militants as young as eight years old and a 2001 FARC training video depicted boys as young as 11 working with missiles. The group has also taken in children from Venezuela, Panama, and Ecuador.
The Colombian government's security forces do not officially recruit children as the legal age for both compulsory and voluntary recruitment has been set at 18. However, students were allowed to enroll as cadets in military secondary schools and 16- or 17-year-olds could enter air force or national army training programs, respectively. In addition, captured enemy child combatants were employed by the Colombian military for intelligence gathering purposes in potential violation of legal prohibitions.
The demobilization efforts targeted toward the FARC in 2016–2017 have provided hope that the conflict will come to an end, limiting the number of children involved in violence. However, other armed groups have yet to be demobilized, and conflict is not yet resolved.

Cuba: In Cuba, compulsory military service for both boys and girls starts at age 17. Male teenagers are allowed to join the Territorial Troops Militia prior to their compulsory service.

Guatemala: Children can join the military at 17 in Guatemala. (CIA World Factbook - 2024).

Haiti: In Haiti an unknown number of children participate in various loosely organised armed groups that are engaged in political violence.

Mexico: In Mexico an unknown number of children are used by criminal organizations like the Gulf Cartel in the Mexican drug war to fight the government and the other rival cartels. Also the Grupos de autodefensa comunitaria recruited some children to defend their villages from the violence of the local crime groups, one of the self-defense groups that recruit soldier children is Coordinadora Regional de Autoridades Comunitarias-Pueblos Fundadores (CRAC-PF) to fight with Los Ardillos, a criminal group split from the Beltrán Leyva Cartel. The battles between CRAC-PF and Los Ardillos caused 53 deaths.

Paraguay: The government of Paraguay accused the guerrilla groups EPP and the ACA of recruit child soldiers to fight the government in the ongoing insurgency in the northeastern part of the country.

United States: In the United States 17-year-olds may join the armed forces with the written agreement of parents. As of 2015 approximately 16,000 17-year-olds were being enlisted annually.
The US Army describes outreach to schools as the 'cornerstone' of its approach to recruitment, and the No Child Left Behind Act gives recruiters the legal right of access to all school students' contact details. Children's rights bodies have criticized the US' reliance on children to staff its armed forces. The committee on the Rights of the Child has recommended that the US raise the minimum age of enlistment to 18.
In negotiations on the OPAC treaty during the 1990s the US joined the UK in strongly opposing a global minimum enlistment age of 18. As a consequence the treaty specified a minimum age of 16. The US ratified the treaty in 2002 (but as of 2018 U.S. ratification of the Convention on the Rights of the Child has not happened).
Per OPAC, US military personnel are normally prohibited from direct participation in hostilities until the age of 18. Still, they are eligible for 'forward deployment', which means that they may be posted to a combat zone to perform support tasks. The committee on the Rights of the Child has called on the US to change this policy and ensure that no minor can be deployed to a forward operating area in a combat zone.
In 2003 and 2004 approximately 60 underage personnel were deployed to Afghanistan and Iraq in error. The Department of Defense subsequently stated that "the situations were immediately rectified and action taken to prevent recurrence."
In 2008 President George W. Bush signed the Child Soldiers Protection Act into law. The law criminalizes leading a military force which recruits child soldiers. It also prohibits arms sales to countries where children are used for military purposes. The law's definition of child soldiers includes "any person under 18 years of age who takes a direct part in hostilities as a member of governmental armed forces." Waivers from the act were issued by both the Obama and Trump administrations.

Asia: In 2004 the Coalition to Stop the Use of Child Soldiers (now Child Soldiers International) reported that in Asia thousands of children are involved in fighting forces in active conflict and ceasefire situations in Afghanistan, Myanmar, Indonesia, Laos, Philippines, Nepal and Sri Lanka. Government refusal of access to conflict zones has made it impossible to document the numbers involved. In 2004 Myanmar was unique in the region as the only country where government armed forces forcibly recruited and used children between the ages of 12 and 16. Johnny and Luther Htoo, twin brothers who jointly led the God's Army guerrilla group, were estimated to have been around ten years old when they began leading the group in 1997.

Afghanistan: Militias recruited thousands of child soldiers during the Afghan civil war over three decades. Many are still fighting now for the Taliban. Some of those taken from Islamic religious schools or madrassas, are used as suicide bombers and gunmen. A propaganda video of boys marching in camouflage uniform and using slogans of martyrdom was issued in 2009 by the Afghan Taliban's leadership. This included a eulogy to a 14-year-old Taliban fighter who allegedly killed an American soldier.

Azerbaijan: Children can volunteer for military service at 17, with compulsory military service, for men, at 18.

Bangladesh: Children can join the Army at 16. (CIA Factbook 2024)

Burma/Myanmar: The State Peace and Development Council has asserted that all of its soldiers volunteered and that all of those accepted are 18 or over. According to Human Rights Watch as many as 70,000 boys serve in Burma/Myanmar's national army, the Tatmadaw, with children as young as 11 being forcibly recruited off the streets. Desertion, the group reported, leads to punishments of three to five years in prison or even execution. The group has also stated that about 5,000–7,000 children serve with a range of different armed ethnic opposition groups, most notably in the United Wa State Army. UN Secretary-General Ban Ki-moon released a report in June 2009 mentioning "grave violations" against children in the country by both the rebels and the government. The administration announced on 4 August that they would send a team into Burma/Myanmar to press for more action.

India: The minimum age to join the Indian Army is 17 and a half.

Iran: Current Iranian law officially prohibits the recruitment of those under 16.
During the Iran–Iraq War, male children were drafted into the Basij army where, according to critics of the Iranian government, they "were sent to the front as waves of human shields". Other sources have estimated the total number of all Iranian casualties to be in the 200,000–600,000 range. One source estimates that 3% of the Iran–Iraq War's casualties were under the age of 14.
There were male Iranian children who left school and participated in the Iran–Iraq War without the knowledge of their parents, including Mohammad Hossein Fahmideh.