diff --git a/Cargo.lock b/Cargo.lock
index 02d1318ea35..1c5d722688a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3177,7 +3177,7 @@ dependencies = [
 
 [[package]]
 name = "libp2p-quic"
-version = "0.12.0"
+version = "0.12.1"
 dependencies = [
  "async-std",
  "futures",
diff --git a/Cargo.toml b/Cargo.toml
index 926e79b4597..4c1b28f6bd6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -93,7 +93,7 @@ libp2p-perf = { version = "0.4.0", path = "protocols/perf" }
 libp2p-ping = { version = "0.46.0", path = "protocols/ping" }
 libp2p-plaintext = { version = "0.43.0", path = "transports/plaintext" }
 libp2p-pnet = { version = "0.26.0", path = "transports/pnet" }
-libp2p-quic = { version = "0.12.0", path = "transports/quic" }
+libp2p-quic = { version = "0.12.1", path = "transports/quic" }
 libp2p-relay = { version = "0.19.1", path = "protocols/relay" }
 libp2p-rendezvous = { version = "0.16.0", path = "protocols/rendezvous" }
 libp2p-request-response = { version = "0.28.1", path = "protocols/request-response" }
diff --git a/transports/quic/CHANGELOG.md b/transports/quic/CHANGELOG.md
index 6e45e002de2..42b358590c0 100644
--- a/transports/quic/CHANGELOG.md
+++ b/transports/quic/CHANGELOG.md
@@ -1,3 +1,10 @@
+## 0.12.1
+
+<!-- Update to libp2p-core v0.43.0 -->
+
+- Deprecate `Config::support_draft_29`.
+  See [PR 5786](https://github.com/libp2p/rust-libp2p/pull/5786).
+
 ## 0.12.0
 
 <!-- Update to libp2p-core v0.43.0 -->
diff --git a/transports/quic/Cargo.toml b/transports/quic/Cargo.toml
index f6f95800193..d0f0d3db406 100644
--- a/transports/quic/Cargo.toml
+++ b/transports/quic/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "libp2p-quic"
-version = "0.12.0"
+version = "0.12.1"
 authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2021"
 rust-version = { workspace = true }
diff --git a/transports/quic/src/config.rs b/transports/quic/src/config.rs
index c623632ddc6..85b89cf35e3 100644
--- a/transports/quic/src/config.rs
+++ b/transports/quic/src/config.rs
@@ -59,6 +59,7 @@ pub struct Config {
     /// If support for draft-29 is enabled servers support draft-29 and version 1 on all
     /// QUIC listening addresses.
     /// As client the version is chosen based on the remote's address.
+    #[deprecated(note = "QUIC draft versions are no longer supported")]
     pub support_draft_29: bool,
 
     /// TLS client config for the inner [`quinn::ClientConfig`].
@@ -72,6 +73,7 @@ pub struct Config {
     mtu_discovery_config: Option<MtuDiscoveryConfig>,
 }
 
+#[expect(deprecated)]
 impl Config {
     /// Creates a new configuration object with default values.
     pub fn new(keypair: &libp2p_identity::Keypair) -> Self {
@@ -122,6 +124,7 @@ pub(crate) struct QuinnConfig {
     pub(crate) endpoint_config: quinn::EndpointConfig,
 }
 
+#[expect(deprecated)]
 impl From<Config> for QuinnConfig {
     fn from(config: Config) -> QuinnConfig {
         let Config {
diff --git a/transports/quic/src/transport.rs b/transports/quic/src/transport.rs
index 84aaba8b672..b42e0b13591 100644
--- a/transports/quic/src/transport.rs
+++ b/transports/quic/src/transport.rs
@@ -84,6 +84,7 @@ pub struct GenTransport<P: Provider> {
     hole_punch_attempts: HashMap<SocketAddr, oneshot::Sender<Connecting>>,
 }
 
+#[expect(deprecated)]
 impl<P: Provider> GenTransport<P> {
     /// Create a new [`GenTransport`] with the given [`Config`].
     pub fn new(config: Config) -> Self {
diff --git a/transports/quic/tests/smoke.rs b/transports/quic/tests/smoke.rs
index 6be4796612a..ed2ff981634 100644
--- a/transports/quic/tests/smoke.rs
+++ b/transports/quic/tests/smoke.rs
@@ -295,6 +295,7 @@ fn concurrent_connections_and_streams_tokio() {
         .quickcheck(prop::<quic::tokio::Provider> as fn(_, _) -> _);
 }
 
+#[expect(deprecated)]
 #[cfg(feature = "tokio")]
 #[tokio::test]
 async fn draft_29_support() {