diff --git a/src/flb_http_client.c b/src/flb_http_client.c
index d17c45d6b4d..5cb434abad3 100644
--- a/src/flb_http_client.c
+++ b/src/flb_http_client.c
@@ -1030,7 +1030,7 @@ static void http_headers_destroy(struct flb_http_client *c)
 int flb_http_set_keepalive(struct flb_http_client *c)
 {
     /* check if 'keepalive' mode is enabled in the Upstream connection */
-    if (flb_stream_is_keepalive(c->u_conn->stream)) {
+    if (flb_stream_is_keepalive(c->u_conn->stream) == FLB_FALSE) {
         return -1;
     }
 
@@ -1149,6 +1149,9 @@ int flb_http_do(struct flb_http_client *c, size_t *bytes)
     size_t bytes_body = 0;
     char *tmp;
 
+    /* Try to add keep alive header */
+    flb_http_set_keepalive(c);
+
     /* Append pending headers */
     ret = http_headers_compose(c);
     if (ret == -1) {
diff --git a/src/flb_output.c b/src/flb_output.c
index 97b26e59eb3..91e83f9868c 100644
--- a/src/flb_output.c
+++ b/src/flb_output.c
@@ -1310,6 +1310,10 @@ int flb_output_upstream_set(struct flb_upstream *u, struct flb_output_instance *
         flags |= FLB_IO_IPV6;
     }
 
+    if (ins->net_setup.keepalive == FLB_TRUE) {
+        flags |= FLB_IO_TCP_KA;
+    }
+
     /* Set flags */
     flb_stream_enable_flags(&u->base, flags);
 
diff --git a/tests/internal/http_client.c b/tests/internal/http_client.c
index 3013c75602b..f6d197cc611 100644
--- a/tests/internal/http_client.c
+++ b/tests/internal/http_client.c
@@ -34,7 +34,7 @@ struct test_ctx* test_ctx_create()
         return NULL;
     }
 
-    ret_ctx->u = flb_upstream_create(ret_ctx->config, "127.0.0.1", 80, 0, NULL);
+    ret_ctx->u = flb_upstream_create(ret_ctx->config, "127.0.0.1", 80, FLB_IO_TCP_KA, NULL);
     if (!TEST_CHECK(ret_ctx->u != NULL)) {
         TEST_MSG("flb_upstream_create failed");
         flb_config_exit(ret_ctx->config);