This paper defines an approximation to the value of funding ratio put options for pension funds.This option is, by construction, the ideal option to hedge the risk of a funding ratio falling below some required minimum level. It’s value can be used for several applications, for example as a riskmeasure for internal risk management or regulation, as a benchmark for (other) derivative solutions to hedge insolvency risks, or to value guarantees made by sponsors to eliminate a funding shortfall.A numerical example shows that the impact of the presence of mortality volatility risk on the value of funding ratio put options is significant.