diff --git a/include/zephyr/posix/pthread.h b/include/zephyr/posix/pthread.h
index 4186aefba555d40..6797442eaef60d8 100644
--- a/include/zephyr/posix/pthread.h
+++ b/include/zephyr/posix/pthread.h
@@ -22,8 +22,8 @@ extern "C" {
 #endif
 
 /* Pthread detach/joinable */
-#define PTHREAD_CREATE_JOINABLE     1
-#define PTHREAD_CREATE_DETACHED     2
+#define PTHREAD_CREATE_DETACHED 0
+#define PTHREAD_CREATE_JOINABLE 1
 
 /* Pthread cancellation */
 #define _PTHREAD_CANCEL_POS	0
diff --git a/lib/posix/posix_internal.h b/lib/posix/posix_internal.h
index 2351d94a994416a..cdabf5bae0c856e 100644
--- a/lib/posix/posix_internal.h
+++ b/lib/posix/posix_internal.h
@@ -25,12 +25,12 @@ struct posix_cond {
 };
 
 enum pthread_state {
-	/* The thread structure is unallocated and available for reuse. */
-	PTHREAD_TERMINATED = 0,
-	/* The thread is running and joinable. */
-	PTHREAD_JOINABLE = PTHREAD_CREATE_JOINABLE,
 	/* The thread is running and detached. */
 	PTHREAD_DETACHED = PTHREAD_CREATE_DETACHED,
+	/* The thread is running and joinable. */
+	PTHREAD_JOINABLE = PTHREAD_CREATE_JOINABLE,
+	/* The thread structure is unallocated and available for reuse. */
+	PTHREAD_TERMINATED,
 	/* A joinable thread exited and its return code is available. */
 	PTHREAD_EXITED
 };
diff --git a/lib/posix/pthread.c b/lib/posix/pthread.c
index 4a803bbfa82ea04..11d3f3d8fad23e3 100644
--- a/lib/posix/pthread.c
+++ b/lib/posix/pthread.c
@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#include <zephyr/init.h>
 #include <zephyr/kernel.h>
 #include <stdio.h>
 #include <zephyr/sys/atomic.h>
@@ -690,3 +691,18 @@ int pthread_getname_np(pthread_t thread, char *name, size_t len)
 	return 0;
 #endif
 }
+
+static int posix_thread_pool_init(const struct device *dev)
+{
+	size_t i;
+
+	ARG_UNUSED(dev);
+
+	for (i = 0; i < CONFIG_MAX_PTHREAD_COUNT; ++i) {
+		posix_thread_pool[i].state = PTHREAD_EXITED;
+	}
+
+	return 0;
+}
+
+SYS_INIT(posix_thread_pool_init, PRE_KERNEL_1, 0);
diff --git a/tests/posix/common/src/pthread.c b/tests/posix/common/src/pthread.c
index facc4a1629a713e..21fc71bb5127ae6 100644
--- a/tests/posix/common/src/pthread.c
+++ b/tests/posix/common/src/pthread.c
@@ -459,9 +459,9 @@ ZTEST(posix_apis, test_posix_pthread_error_condition)
 		      "set scheduling policy error");
 	zassert_equal(pthread_attr_setschedpolicy(&attr, 2),
 		      EINVAL, "set scheduling policy error");
-	zassert_false(pthread_attr_setdetachstate(&attr, 1),
+	zassert_false(pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE),
 		      "set detach state error");
-	zassert_false(pthread_attr_setdetachstate(&attr, 2),
+	zassert_false(pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED),
 		      "set detach state error");
 	zassert_equal(pthread_attr_setdetachstate(&attr, 3),
 		      EINVAL, "set detach state error");