diff --git a/oshmem/mca/atomic/ucx/atomic_ucx_module.c b/oshmem/mca/atomic/ucx/atomic_ucx_module.c
index 172626dd0c6..ed95431f5a4 100644
--- a/oshmem/mca/atomic/ucx/atomic_ucx_module.c
+++ b/oshmem/mca/atomic/ucx/atomic_ucx_module.c
@@ -29,12 +29,19 @@ static ucp_request_param_t mca_spml_ucp_request_params[] = {
 };
 #endif
 
+static int mca_atomic_ucx_nb_support = 0;
+
 /*
  * Initial query function that is invoked during initialization, allowing
  * this module to indicate what level of thread support it provides.
  */
 int mca_atomic_ucx_startup(bool enable_progress_threads, bool enable_threads)
 {
+    unsigned major, minor, release_number;
+    ucp_get_version(&major, &minor, &release_number);
+
+    mca_atomic_ucx_nb_support = UCX_VERSION(major, minor, release_number) >= UCX_VERSION(1, 20, 0);
+
     return OSHMEM_SUCCESS;
 }
 
@@ -73,8 +80,15 @@ int mca_atomic_ucx_op(shmem_ctx_t ctx,
     status_ptr = ucp_atomic_op_nbx(ucx_ctx->ucp_peers[pe].ucp_conn,
                                    op, &value, 1, rva, ucx_mkey->rkey,
                                    &mca_spml_ucp_request_params[size >> 3]);
-    res = opal_common_ucx_wait_request(status_ptr, ucx_ctx->ucp_worker[0],
-                                       "ucp_atomic_op_nbx post");
+    if (mca_atomic_ucx_nb_support) {
+        /* UCX is packing (copying) the value pointer, so there's no need to wait for completion
+           (no stack corruption concerns). Additionally, there's no need to free the status pointer 
+           as its already freed by ucp_atomic_op_nbx when a reply buffer is not provided. */
+        res = UCS_PTR_IS_ERR(status_ptr) ? OSHMEM_ERROR : OSHMEM_SUCCESS;
+    } else {
+        res = opal_common_ucx_wait_request(status_ptr, ucx_ctx->ucp_worker[0], 
+                                           "ucp_atomic_op_nbx");
+    }
 #else
     status = ucp_atomic_post(ucx_ctx->ucp_peers[pe].ucp_conn,
                              op, value, size, rva,
diff --git a/oshmem/mca/spml/ucx/spml_ucx.c b/oshmem/mca/spml/ucx/spml_ucx.c
index e73653b75e1..7973721f429 100644
--- a/oshmem/mca/spml/ucx/spml_ucx.c
+++ b/oshmem/mca/spml/ucx/spml_ucx.c
@@ -1644,19 +1644,77 @@ int mca_spml_ucx_put_all_nb(void *dest, const void *source, size_t size, long *c
     return OSHMEM_SUCCESS;
 }
 
-/* This routine is not implemented */
+
+static inline int mca_spml_ucx_signal(shmem_ctx_t ctx,
+                                      uint64_t *sig_addr,
+                                      uint64_t signal,
+                                      int sig_op,
+                                      int dst)
+{
+    uint64_t dummy_prev;
+
+    if (sig_op == SHMEM_SIGNAL_SET) {
+        return MCA_ATOMIC_CALL(swap(ctx, (void*)sig_addr, (void*)&dummy_prev,
+                                   signal, sizeof(uint64_t), dst));
+    } else if (sig_op == SHMEM_SIGNAL_ADD) {
+        return MCA_ATOMIC_CALL(add(ctx, (void*)sig_addr, signal,
+                                   sizeof(uint64_t), dst));
+    }
+
+    SPML_UCX_ERROR("Invalid signal operation: %d", sig_op);
+    return OSHMEM_ERR_NOT_IMPLEMENTED;
+}
+
+static inline int mca_spml_ucx_signal_nb(shmem_ctx_t ctx,
+                                         uint64_t *sig_addr,
+                                         uint64_t signal,
+                                         int sig_op,
+                                         int dst)
+{
+    uint64_t dummy_prev, dummy_fetch;
+
+    if (sig_op == SHMEM_SIGNAL_SET) {
+        return MCA_ATOMIC_CALL(swap_nb(ctx, &dummy_fetch, (void*)sig_addr, (void*)&dummy_prev,
+                                    signal, sizeof(uint64_t), dst));
+    } else if (sig_op == SHMEM_SIGNAL_ADD) {
+        return MCA_ATOMIC_CALL(fadd_nb(ctx, &dummy_fetch, (void*)sig_addr, (void*)&dummy_prev,
+                                   signal, sizeof(uint64_t), dst));
+    }
+
+    SPML_UCX_ERROR("Invalid signal operation: %d", sig_op);
+    return OSHMEM_ERR_NOT_IMPLEMENTED;
+}
+
 int mca_spml_ucx_put_signal(shmem_ctx_t ctx, void* dst_addr, size_t size, void*
         src_addr, uint64_t *sig_addr, uint64_t signal, int sig_op, int dst)
 {
-    return OSHMEM_ERR_NOT_IMPLEMENTED;
+    int res;
+
+    res = mca_spml_ucx_put(ctx, dst_addr, size, src_addr, dst);
+    if (OPAL_UNLIKELY(OSHMEM_SUCCESS != res)) {
+        return res;
+    }
+
+    return mca_spml_ucx_signal(ctx, sig_addr, signal, sig_op, dst);
 }
 
-/* This routine is not implemented */
 int mca_spml_ucx_put_signal_nb(shmem_ctx_t ctx, void* dst_addr, size_t size,
         void* src_addr, uint64_t *sig_addr, uint64_t signal, int sig_op, int
         dst)
 {
-    return OSHMEM_ERR_NOT_IMPLEMENTED;
+    int res;
+
+    res = mca_spml_ucx_put_nb(ctx, dst_addr, size, src_addr, dst, NULL);
+    if (OPAL_UNLIKELY(OSHMEM_SUCCESS != res)) {
+        return res;
+    }
+
+    res = mca_spml_ucx_fence(ctx);
+    if (OPAL_UNLIKELY(OSHMEM_SUCCESS != res)) {
+        return res;
+    }
+
+    return mca_spml_ucx_signal_nb(ctx, sig_addr, signal, sig_op, dst);
 }
 
 /* This routine is not implemented */