diff --git a/cortex-ar/CHANGELOG.md b/cortex-ar/CHANGELOG.md
index 40dc992..de9680f 100644
--- a/cortex-ar/CHANGELOG.md
+++ b/cortex-ar/CHANGELOG.md
@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - MMU code: Use more `arbitrary-int` types for MMU configuration bits.
 - Renamed `L1Section::new` to `L1Section::new_with_addr_and_attrs`.
+- Bumped `defmt` to v1
 
 ## [v0.2.0]
 
diff --git a/cortex-ar/Cargo.toml b/cortex-ar/Cargo.toml
index 9b1f353..04066ba 100644
--- a/cortex-ar/Cargo.toml
+++ b/cortex-ar/Cargo.toml
@@ -30,7 +30,7 @@ bitbybit = "1.3.3"
 num_enum = { version = "0.7", default-features = false }
 critical-section = {version = "1.2.0", features = ["restore-state-u8"], optional = true}
 thiserror = { version = "2", default-features = false }
-defmt = {version = "0.3", optional = true}
+defmt = {version = "1", optional = true}
 
 [build-dependencies]
 arm-targets = {version = "0.2.0", path = "../arm-targets"}