A tontine () is an investment linked to a living person which provides an income for as long as that person is alive. Such schemes originated as plans for governments to raise capital in the 17th century and became relatively widespread in the 18th and 19th centuries.

Tontines enable subscribers to share the risk of living a long life by combining features of a group annuity with a kind of mortality lottery. Each subscriber pays a sum into a trust and thereafter receives a periodical payout. As members die, their payout entitlements devolve to the other participants, and so the value of each continuing payout increases. On the death of the final member, the trust scheme is usually wound up.

Tontines are still common in France. They can be issued by European insurers under the Directive 2002/83/EC of the European Parliament. The Pan-European Pension Regulation passed by the European Commission in 2019 also contains provisions that specifically permit next-generation pension products that abide by the "tontine principle" to be offered in the 27 EU member states.

Questionable practices by U.S. life insurers in 1906 led to the Armstrong Investigation in the United States restricting some forms of tontines. Nevertheless, in March 2017, The New York Times reported that tontines were getting fresh consideration as a way for people to get steady retirement income.