diff --git a/tests/net/lib/coap_client/CMakeLists.txt b/tests/net/lib/coap_client/CMakeLists.txt
index 6e3b6353e08..9ed7926a204 100644
--- a/tests/net/lib/coap_client/CMakeLists.txt
+++ b/tests/net/lib/coap_client/CMakeLists.txt
@@ -26,7 +26,7 @@ add_compile_definitions(CONFIG_COAP_CLIENT_MESSAGE_HEADER_SIZE=48)
 add_compile_definitions(CONFIG_COAP_CLIENT_STACK_SIZE=1024)
 add_compile_definitions(CONFIG_COAP_CLIENT_THREAD_PRIORITY=10)
 add_compile_definitions(CONFIG_COAP_LOG_LEVEL=4)
-add_compile_definitions(CONFIG_COAP_INIT_ACK_TIMEOUT_MS=100)
+add_compile_definitions(CONFIG_COAP_INIT_ACK_TIMEOUT_MS=1000)
 add_compile_definitions(CONFIG_COAP_CLIENT_MAX_REQUESTS=2)
 add_compile_definitions(CONFIG_COAP_CLIENT_MAX_INSTANCES=2)
 add_compile_definitions(CONFIG_COAP_MAX_RETRANSMIT=4)
diff --git a/tests/net/lib/coap_client/boards/native_sim.conf b/tests/net/lib/coap_client/boards/native_sim.conf
new file mode 100644
index 00000000000..0843e94acbd
--- /dev/null
+++ b/tests/net/lib/coap_client/boards/native_sim.conf
@@ -0,0 +1 @@
+CONFIG_NATIVE_SIM_SLOWDOWN_TO_REAL_TIME=y
diff --git a/tests/net/lib/coap_client/src/main.c b/tests/net/lib/coap_client/src/main.c
index 2f3fa28ebff..72b84a60f5e 100644
--- a/tests/net/lib/coap_client/src/main.c
+++ b/tests/net/lib/coap_client/src/main.c
@@ -8,7 +8,9 @@
 #include <zephyr/logging/log.h>
 #include <zephyr/misc/lorem_ipsum.h>
 #include <zephyr/ztest.h>
-
+#if defined(CONFIG_NATIVE_SIM_SLOWDOWN_TO_REAL_TIME)
+#include "timer_model.h"
+#endif
 #include "stubs.h"
 
 LOG_MODULE_REGISTER(coap_client_test, LOG_LEVEL_DBG);
@@ -16,12 +18,12 @@ LOG_MODULE_REGISTER(coap_client_test, LOG_LEVEL_DBG);
 DEFINE_FFF_GLOBALS;
 #define FFF_FAKES_LIST(FAKE)
 
-#define LONG_ACK_TIMEOUT_MS                 200
+#define LONG_ACK_TIMEOUT_MS                 (2 * CONFIG_COAP_INIT_ACK_TIMEOUT_MS)
 #define MORE_THAN_EXCHANGE_LIFETIME_MS      4 * CONFIG_COAP_INIT_ACK_TIMEOUT_MS
 #define MORE_THAN_LONG_EXCHANGE_LIFETIME_MS 4 * LONG_ACK_TIMEOUT_MS
 #define MORE_THAN_ACK_TIMEOUT_MS                                                                   \
 	(CONFIG_COAP_INIT_ACK_TIMEOUT_MS + CONFIG_COAP_INIT_ACK_TIMEOUT_MS / 2)
-#define COAP_SEPARATE_TIMEOUT (6000 * 3) /* Needs a safety marging, tests run faster than -rt */
+#define COAP_SEPARATE_TIMEOUT (6000 * 2) /* Needs a safety marging, tests run faster than -rt */
 #define VALID_MESSAGE_ID BIT(31)
 #define TOKEN_OFFSET          4
 
@@ -425,6 +427,13 @@ extern void net_coap_init(void);
 
 static void *suite_setup(void)
 {
+#if defined(CONFIG_NATIVE_SIM_SLOWDOWN_TO_REAL_TIME)
+	/* It is enough that some slow-down is happening on sleeps, it does not have to be
+	 * real time
+	 */
+	hwtimer_set_rt_ratio(100.0);
+	k_sleep(K_MSEC(1));
+#endif
 	net_coap_init();
 	zassert_ok(coap_client_init(&client, NULL));
 	zassert_ok(coap_client_init(&client2, NULL));
diff --git a/tests/net/lib/coap_client/src/stubs.c b/tests/net/lib/coap_client/src/stubs.c
index 8d251157ac1..76289991155 100644
--- a/tests/net/lib/coap_client/src/stubs.c
+++ b/tests/net/lib/coap_client/src/stubs.c
@@ -7,7 +7,7 @@
 #include <zephyr/logging/log.h>
 #include <stubs.h>
 
-LOG_MODULE_DECLARE(coap_client_test);
+LOG_MODULE_DECLARE(coap_client_test, LOG_LEVEL_DBG);
 
 DEFINE_FAKE_VALUE_FUNC(uint32_t, z_impl_sys_rand32_get);
 DEFINE_FAKE_VALUE_FUNC(ssize_t, z_impl_zsock_recvfrom, int, void *, size_t, int, struct sockaddr *,
@@ -45,6 +45,9 @@ int z_impl_zvfs_poll(struct zvfs_pollfd *fds, int nfds, int poll_timeout)
 			events++;
 		}
 	}
+	if (events == 0) {
+		k_sleep(K_MSEC(poll_timeout));
+	}
 
 	return events;
 }