diff --git a/CHANGELOG.md b/CHANGELOG.md
index b8eb428..fe2aad8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,8 @@ All notable changes to this project will be documented in this file. The format
 
 ## [Unreleased]
 
+## [2.1.1] - 2024-01-03
+
 ### Changed
 - Rename internal matrix square-root from `stretch_2` and `stretch_2s` to `sqrt_2` and `sqrt_2s`. This does not affect the public API which remains unchanged as (matrix) square root `sqrt(T)`.
 - Remove an unused print statement in `sqrt_2()`.