diff --git a/Cargo.lock b/Cargo.lock
index 97ab84e2..deac62e6 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1892,9 +1892,9 @@ checksum = "af150ab688ff2122fcef229be89cb50dd66af9e01a4ff320cc137eecc9bacc38"
 
 [[package]]
 name = "janus_messages"
-version = "0.5.20"
+version = "0.5.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4c7269662cdac52cea2a98cf10cb35028d1d673951e4ff1bcf8c653b5d3b8577"
+checksum = "f47df94bc0ecd0ec7991986a83dcdc98e54629905d293aafe9cd850c0aeea419"
 dependencies = [
  "anyhow",
  "base64 0.21.4",
diff --git a/Cargo.toml b/Cargo.toml
index 0655eeab..82f5cb4e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -26,7 +26,7 @@ env_logger = "0.10.0"
 fastrand = "2.0.0"
 futures-lite = "1.13.0"
 git-version = "0.3.5"
-janus_messages = "0.5.20"
+janus_messages = "0.5.21"
 log = "0.4.20"
 opentelemetry = { version = "0.19.0", features = ["metrics"] }
 opentelemetry-prometheus = { version = "0.12.0", features = [
diff --git a/client/Cargo.toml b/client/Cargo.toml
index cf0ead2b..30271d5a 100644
--- a/client/Cargo.toml
+++ b/client/Cargo.toml
@@ -24,7 +24,7 @@ uuid = { version = "1.4.1", features = ["v4", "fast-rng", "serde"] }
 time = { version = "0.3.29", features = ["serde", "serde-well-known"] }
 log = "0.4.20"
 pad-adapter = "0.1.1"
-janus_messages = "0.5.20"
+janus_messages = "0.5.21"
 
 [dev-dependencies]
 divviup-api = { version = "*", path = ".." }