diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e93ecb3..58d2c39 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -34,7 +34,7 @@ jobs:
           # https://github.com/rust-lang/libs-team/issues/72.
           # This test target is here so that we notice if we accidentally bump
           # the MSRV, but it's not a promise that we won't bump it.
-          "1.66.1",
+          "1.72.0",
         ]
 
     steps:
diff --git a/Cargo.toml b/Cargo.toml
index 14b1d65..cf91480 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,7 +8,7 @@ license = "CC0-1.0 OR Apache-2.0"
 documentation = "https://docs.rs/blake3"
 readme = "README.md"
 edition = "2021"
-rust-version = "1.66.1"
+rust-version = "1.72.0"
 
 [features]
 default = ["std"]
diff --git a/test_vectors/Cargo.toml b/test_vectors/Cargo.toml
index 3db2bb6..4441784 100644
--- a/test_vectors/Cargo.toml
+++ b/test_vectors/Cargo.toml
@@ -2,7 +2,7 @@
 name = "test_vectors"
 version = "0.0.0"
 edition = "2021"
-rust-version = "1.66.1"
+rust-version = "1.72.0"
 
 [features]
 neon = ["blake3/neon"]