diff --git a/include/mbedtls/config_adjust_ssl.h b/include/mbedtls/config_adjust_ssl.h
index 2221e5b2e7..36641e18b6 100644
--- a/include/mbedtls/config_adjust_ssl.h
+++ b/include/mbedtls/config_adjust_ssl.h
@@ -51,7 +51,6 @@
 #if !defined(MBEDTLS_SSL_PROTO_DTLS)
 #undef MBEDTLS_SSL_DTLS_ANTI_REPLAY
 #undef MBEDTLS_SSL_DTLS_CONNECTION_ID
-#undef MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT
 #undef MBEDTLS_SSL_DTLS_HELLO_VERIFY
 #undef MBEDTLS_SSL_DTLS_SRTP
 #undef MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE
diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index d18d0fadb8..827b96165f 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -533,28 +533,6 @@
  */
 #define MBEDTLS_SSL_DTLS_CONNECTION_ID
 
-/**
- * \def MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT
- *
- * Defines whether RFC 9146 (default) or the legacy version
- * (version draft-ietf-tls-dtls-connection-id-05,
- * https://tools.ietf.org/html/draft-ietf-tls-dtls-connection-id-05)
- * is used.
- *
- * Set the value to 0 for the standard version, and
- * 1 for the legacy draft version.
- *
- * \deprecated Support for the legacy version of the DTLS
- *             Connection ID feature is deprecated. Please
- *             switch to the standardized version defined
- *             in RFC 9146 enabled by utilizing
- *             MBEDTLS_SSL_DTLS_CONNECTION_ID without use
- *             of MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT.
- *
- * Requires: MBEDTLS_SSL_DTLS_CONNECTION_ID
- */
-#define MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT 0
-
 /**
  * \def MBEDTLS_SSL_DTLS_HELLO_VERIFY
  *
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 7ea0174612..4bfe4af02c 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -470,14 +470,6 @@
 
 /** \} name SECTION: Module settings */
 
-/*
- * Default to standard CID mode
- */
-#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) && \
-    !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT)
-#define MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT 0
-#endif
-
 /*
  * Length of the verify data for secure renegotiation
  */
@@ -649,11 +641,7 @@
 #define MBEDTLS_TLS_EXT_SIG_ALG_CERT                50 /* RFC 8446 TLS 1.3 */
 #define MBEDTLS_TLS_EXT_KEY_SHARE                   51 /* RFC 8446 TLS 1.3 */
 
-#if MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT == 0
 #define MBEDTLS_TLS_EXT_CID                         54 /* RFC 9146 DTLS 1.2 CID */
-#else
-#define MBEDTLS_TLS_EXT_CID                        254 /* Pre-RFC 9146 DTLS 1.2 CID */
-#endif
 
 #define MBEDTLS_TLS_EXT_ECJPAKE_KKPP               256 /* experimental */
 
diff --git a/library/mbedtls_check_config.h b/library/mbedtls_check_config.h
index 5e5a5b31db..43c2308800 100644
--- a/library/mbedtls_check_config.h
+++ b/library/mbedtls_check_config.h
@@ -238,19 +238,6 @@
 #error "MBEDTLS_SSL_CID_OUT_LEN_MAX too large (max 255)"
 #endif
 
-#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT)     &&                 \
-    !defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
-#error "MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT defined, but not all prerequisites"
-#endif
-
-#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT) && MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT != 0
-#if defined(MBEDTLS_DEPRECATED_REMOVED)
-#error "MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT is deprecated and will be removed in a future version of Mbed TLS"
-#elif defined(MBEDTLS_DEPRECATED_WARNING)
-#warning "MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT is deprecated and will be removed in a future version of Mbed TLS"
-#endif
-#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT && MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT != 0 */
-
 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC) &&   \
     !defined(MBEDTLS_SSL_PROTO_TLS1_2)
 #error "MBEDTLS_SSL_ENCRYPT_THEN_MAC defined, but not all prerequisites"
diff --git a/library/ssl_msg.c b/library/ssl_msg.c
index 5774bfc865..5eeb154047 100644
--- a/library/ssl_msg.c
+++ b/library/ssl_msg.c
@@ -663,8 +663,7 @@ static void ssl_extract_add_data_from_record(unsigned char *add_data,
     unsigned char *cur = add_data;
     size_t ad_len_field = rec->data_len;
 
-#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) && \
-    MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT == 0
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     const unsigned char seq_num_placeholder[] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
 #endif
 
@@ -680,8 +679,7 @@ static void ssl_extract_add_data_from_record(unsigned char *add_data,
         ((void) tls_version);
         ((void) taglen);
 
-#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) && \
-        MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT == 0
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
         if (rec->cid_len != 0) {
             // seq_num_placeholder
             memcpy(cur, seq_num_placeholder, sizeof(seq_num_placeholder));
@@ -711,8 +709,7 @@ static void ssl_extract_add_data_from_record(unsigned char *add_data,
     memcpy(cur, rec->ver, sizeof(rec->ver));
     cur += sizeof(rec->ver);
 
-#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) && \
-    MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT == 1
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 
     if (rec->cid_len != 0) {
         // CID
@@ -727,8 +724,7 @@ static void ssl_extract_add_data_from_record(unsigned char *add_data,
         MBEDTLS_PUT_UINT16_BE(ad_len_field, cur, 0);
         cur += 2;
     } else
-#elif defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) && \
-    MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT == 0
+#elif defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 
     if (rec->cid_len != 0) {
         // epoch + sequence number
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index dee80292e2..ecc9187af2 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2633,18 +2633,6 @@ void mbedtls_ssl_get_dtls_srtp_negotiation_result(const mbedtls_ssl_context *ssl
 }
 #endif /* MBEDTLS_SSL_DTLS_SRTP */
 
-#if !defined(MBEDTLS_DEPRECATED_REMOVED)
-void mbedtls_ssl_conf_max_version(mbedtls_ssl_config *conf, int major, int minor)
-{
-    conf->max_tls_version = (mbedtls_ssl_protocol_version) ((major << 8) | minor);
-}
-
-void mbedtls_ssl_conf_min_version(mbedtls_ssl_config *conf, int major, int minor)
-{
-    conf->min_tls_version = (mbedtls_ssl_protocol_version) ((major << 8) | minor);
-}
-#endif /* MBEDTLS_DEPRECATED_REMOVED */
-
 #if defined(MBEDTLS_SSL_SRV_C)
 void mbedtls_ssl_conf_cert_req_ca_list(mbedtls_ssl_config *conf,
                                        char cert_req_ca_list)
diff --git a/tests/configs/tls13-only.h b/tests/configs/tls13-only.h
index 342bbed91e..8260ef5e12 100644
--- a/tests/configs/tls13-only.h
+++ b/tests/configs/tls13-only.h
@@ -25,4 +25,3 @@
 #undef MBEDTLS_SSL_DTLS_SRTP
 #undef MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE
 #undef MBEDTLS_SSL_DTLS_CONNECTION_ID
-#undef MBEDTLS_SSL_DTLS_CONNECTION_ID_COMPAT