How Long Do Garter Snakes Live?
Garter snakes are commonly given a captive lifespan of six to ten years, which is shorter than most pet colubrids. The single largest avoidable cause of early death in captive garters is dietary rather than environmental.
Published lifespan figures
| Figure | Value | Notes |
|---|---|---|
| Commonly published in captivity | 6-10 years | Shorter than most pet colubrids |
| Well-kept animals | Toward the upper end, sometimes beyond | Husbandry-dependent |
| Wild | Considerably shorter | High predation |
Checked September 20, 2026 against the sources at the foot of this page. Where sources differ the range is shown rather than averaged.
What actually shortens it
Published lifespans describe well-kept animals. The gap between the figure above and what a garter snake actually lives is almost entirely husbandry, and these are the levers that matter most.
Thiaminase from the wrong fish
The species-specific one, and it is a genuine killer. Goldfish, fathead minnows, tuna and bream contain thiaminase, which destroys vitamin B1. The resulting deficiency is neurological and progressive: seizures, star-gazing and death.
Monotonous diet
Even using safe fish, a single-item diet risks deficiency in a way a rodent-fed colubrid's does not. Whole fish, earthworms and occasional pink mice between them cover what one item cannot.
Unregulated heat
Thermal burns are among the most common reptile injuries, and snakes are particularly exposed because they coil against a heat source rather than moving off it. Every heat source on a thermostat.
Common questions
How long do garter snakes live?
Commonly six to ten years in captivity, which is shorter than corn snakes or kingsnakes. Well-kept animals reach the upper end and sometimes beyond, and wild lifespans are considerably shorter.
What is the biggest threat to a captive garter snake's life?
Thiaminase. Goldfish, fathead minnows, tuna and bream contain an enzyme that destroys vitamin B1, and a garter snake fed on them develops a progressive neurological deficiency that is ultimately fatal.
Why do garter snakes live shorter lives than corn snakes?
Published captive figures are lower, and dietary complexity is part of it: a rodent-fed colubrid is easy to feed correctly, whereas a garter snake's fish-and-worm diet has more ways to go wrong.