A suicide method is any means by which a person may choose to end their life. Suicide attempts do not always result in death, and a non-fatal suicide attempt can leave the person with serious physical injuries, long-term health problems, or brain damage.

Worldwide, three suicide methods predominate, with the pattern varying in different countries: these are hanging, pesticides, and firearms. Some suicides may be preventable by removing the means. Making common suicide methods less accessible leads to an overall reduction in the number of suicides.

Method-specific ways to do this might include restricting access to pesticides, firearms, and commonly used drugs. Other important measures are the introduction of policies that address the misuse of alcohol and the treatment of mental disorders. Gun-control measures in a number of countries have seen a reduction in suicides and other gun-related deaths. Other preventive measures are not method-specific; these include support, access to treatment, and calling a crisis hotline. There are multiple talk therapies that reduce suicidal thoughts and behaviors regardless of method, including dialectical behavior therapy (DBT).

The study of suicide methods aims to identify those commonly used, and the groups at risk of suicide; making methods less accessible may be useful in suicide prevention. Limiting the availability of means such as pesticides and firearms is recommended by a World Health Report on suicide and its prevention. The early identification of mental disorders and substance abuse disorders, follow-up care for those who have attempted suicide, and responsible reporting by the media are all seen to be key in reducing the number of deaths by suicide. National suicide prevention strategies are also advocated using a comprehensive and coordinated response to suicide prevention. This needs to include the registration and monitoring of suicides and attempted suicide, breaking figures down by age, sex, and method.

Such information allows public health resources to focus on the problems that are relevant in a particular place, or for a given population or subpopulation. For instance, if firearms are used in a significant number of suicides in one place, then public health policies there could focus on gun safety, such as keeping guns locked away, and the key inaccessible to at-risk family members. If young people are found to be at increased risk of suicide by overdosing on particular medications, then an alternative class of medication may be prescribed instead, a safety plan and monitoring of medication can be put in place, and parents can be educated about how to prevent the hoarding of medication for a future suicide attempt.

Media reporting of the methods used in any given suicide is "strongly discouraged" by the World Health Organization, government health agencies, universities, and the Associated Press among others. Detailed descriptions of suicides or the personal characteristics of the person who died contribute to copycat suicides (suicide contagion). Dramatic or inappropriate descriptions of individual suicides by mass media has been linked specifically to copycat suicides among teenagers. Writing for The New Yorker about celebrity suicides, Andrew Solomon wrote that "You who are reading this are at statistically increased risk of suicide right now." In one study, changes in how news outlets reported suicide reduced suicides by a particular method.

Media reporting guidelines also apply to "online content including citizen-generated media coverage". The Recommendations for Reporting on Suicide, created by journalists, suicide prevention groups, and internet safety non-profit organizations, encourage linking to resources such as a list of suicide crisis lines and information about risk factors for suicide, and reporting on suicide as a multi-faceted, treatable health issue.

Method restriction, also called lethal means reduction, is an effective way to reduce the number of suicide deaths in the short and medium term. Method restriction is considered a best practice supported by "compelling" evidence. Some of these actions, such as installing barriers on bridges and reducing the toxicity in gas, require action by governments, industries, or public utilities. At the individual level, method restriction can be as simple as asking a trusted friend or family member to store firearms until the crisis has passed. According to Danuta Wasserman, professor in psychiatry and suicidology at Karolinska Institute, choosing not to restrict access to suicide methods is unethical.