diff --git a/crates/uv-cache/src/lib.rs b/crates/uv-cache/src/lib.rs
index b4a1391064ee4..b934adb05195c 100644
--- a/crates/uv-cache/src/lib.rs
+++ b/crates/uv-cache/src/lib.rs
@@ -1187,7 +1187,7 @@ impl CacheBucket {
             Self::Interpreter => "interpreter-v4",
             // Note that when bumping this, you'll also need to bump it
             // in `crates/uv/tests/it/cache_clean.rs`.
-            Self::Simple => "simple-v20",
+            Self::Simple => "simple-v21",
             // Note that when bumping this, you'll also need to bump it
             // in `crates/uv/tests/it/cache_prune.rs`.
             Self::Wheels => "wheels-v6",
diff --git a/crates/uv/tests/it/cache_clean.rs b/crates/uv/tests/it/cache_clean.rs
index 2ecab759b6f55..03f812bd0138c 100644
--- a/crates/uv/tests/it/cache_clean.rs
+++ b/crates/uv/tests/it/cache_clean.rs
@@ -139,7 +139,7 @@ fn clean_package_pypi() -> Result<()> {
     // Assert that the `.rkyv` file is created for `iniconfig`.
     let rkyv = context
         .cache_dir
-        .child("simple-v20")
+        .child("simple-v21")
         .child("pypi")
         .child("iniconfig.rkyv");
     assert!(
@@ -213,7 +213,7 @@ fn clean_package_index() -> Result<()> {
     // Assert that the `.rkyv` file is created for `iniconfig`.
     let rkyv = context
         .cache_dir
-        .child("simple-v20")
+        .child("simple-v21")
         .child("index")
         .child("e8208120cae3ba69")
         .child("iniconfig.rkyv");