diff --git a/pkg/tinydtls/Kconfig b/pkg/tinydtls/Kconfig
index 14ef675737..daf62b0fb1 100644
--- a/pkg/tinydtls/Kconfig
+++ b/pkg/tinydtls/Kconfig
@@ -38,6 +38,7 @@ config DTLS_CONTEXT_MAX
 
 config DTLS_PEER_MAX
     int "Max number of peers"
+    default 2 if KCONFIG_USEMODULE_GCOAP_DTLS
     default 1
     help
         The maximum number of DTLS peers.
diff --git a/pkg/tinydtls/Makefile.include b/pkg/tinydtls/Makefile.include
index fda2825bd6..79245a2b98 100644
--- a/pkg/tinydtls/Makefile.include
+++ b/pkg/tinydtls/Makefile.include
@@ -63,6 +63,12 @@ endif
 PEER_MAX := $(or $(CONFIG_DTLS_PEER_MAX),$(patsubst -DCONFIG_DTLS_PEER_MAX=%,%,$(filter -DCONFIG_DTLS_PEER_MAX=%,$(CFLAGS))))
 ifneq (,$(PEER_MAX))
     CFLAGS += -DDTLS_PEER_MAX=$(PEER_MAX)
+else ifneq (,$(filter gcoap_dtls,$(USEMODULE)))
+    # The default value in sys/include/net/dtls.h for CONFIG_DTLS_PEER_MAX is 2
+    # when gcoap_dtls is active, otherwise 1. As the default in tinydtls is 1,
+    # we need to set it explicitly if the dtls.h default value deviates from
+    # the tinydtls default.
+    CFLAGS += -DDTLS_PEER_MAX=2
 endif
 
 HANDSHAKE_MAX := $(or $(CONFIG_DTLS_HANDSHAKE_MAX),$(patsubst -DCONFIG_DTLS_HANDSHAKE_MAX=%,%,$(filter -DCONFIG_DTLS_HANDSHAKE_MAX=%,$(CFLAGS))))
diff --git a/sys/include/net/dtls.h b/sys/include/net/dtls.h
index bfc9dada4e..1e5571dace 100644
--- a/sys/include/net/dtls.h
+++ b/sys/include/net/dtls.h
@@ -36,6 +36,8 @@
 #ifndef NET_DTLS_H
 #define NET_DTLS_H
 
+#include "modules.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -44,8 +46,12 @@ extern "C" {
  * @brief The maximum number DTLS peers (i.e. sessions)
  */
 #ifndef CONFIG_DTLS_PEER_MAX
+#if IS_USED(MODULE_GCOAP_DTLS)
+#define CONFIG_DTLS_PEER_MAX       (2)
+#else
 #define CONFIG_DTLS_PEER_MAX       (1)
 #endif
+#endif
 
 #ifdef __cplusplus
 }