diff --git a/include/openssl/tls1.h b/include/openssl/tls1.h
index 03b218ba..e3958520 100644
--- a/include/openssl/tls1.h
+++ b/include/openssl/tls1.h
@@ -208,7 +208,7 @@ extern "C" {
 // ExtensionType value from draft-ietf-quic-tls. Note that this collides with
 // TLS-LTS and, based on scans, something else too. Since it's QUIC-only, that
 // shouldn't be a problem in practice.
-#define TLSEXT_TYPE_quic_transport_parameters 26
+#define TLSEXT_TYPE_quic_transport_parameters 0xffa5
 
 // ExtensionType value assigned to
 // https://tools.ietf.org/html/draft-ietf-tls-certificate-compression-03
diff --git a/ssl/test/runner/common.go b/ssl/test/runner/common.go
index 56ee0dc3..f77a4ccc 100644
--- a/ssl/test/runner/common.go
+++ b/ssl/test/runner/common.go
@@ -123,7 +123,6 @@ const (
 	extensionPadding                    uint16 = 21
 	extensionExtendedMasterSecret       uint16 = 23
 	extensionTokenBinding               uint16 = 24
-	extensionQUICTransportParams        uint16 = 26 // conflicts with TLS-LTS
 	extensionCompressedCertAlgs         uint16 = 27
 	extensionSessionTicket              uint16 = 35
 	extensionPreSharedKey               uint16 = 41    // draft-ietf-tls-tls13-23
@@ -137,6 +136,7 @@ const (
 	extensionCustom                     uint16 = 1234  // not IANA assigned
 	extensionNextProtoNeg               uint16 = 13172 // not IANA assigned
 	extensionRenegotiationInfo          uint16 = 0xff01
+	extensionQUICTransportParams        uint16 = 0xffa5 // draft-ietf-quic-tls-13
 	extensionChannelID                  uint16 = 30032 // not IANA assigned
 	extensionDummyPQPadding             uint16 = 54537 // not IANA assigned
 )