diff --git a/apollo-router/src/axum_factory/axum_http_server_factory.rs b/apollo-router/src/axum_factory/axum_http_server_factory.rs
index b49d5e7918..4077ddc057 100644
--- a/apollo-router/src/axum_factory/axum_http_server_factory.rs
+++ b/apollo-router/src/axum_factory/axum_http_server_factory.rs
@@ -306,6 +306,9 @@ impl HttpServerFactory for AxumHttpServerFactory {
             if let Some(max_headers) = configuration.supergraph.experimental_http1_max_headers {
                 http_config.http1_max_headers(max_headers);
             }
+            if let Some(max_buf_size) = configuration.supergraph.experimental_http1_max_buf_size {
+                http_config.max_buf_size(max_buf_size);
+            }
 
             let (main_server, main_shutdown_sender) = serve_router_on_listen_addr(
                 main_listener,
diff --git a/apollo-router/src/configuration/mod.rs b/apollo-router/src/configuration/mod.rs
index b744cf9df9..bc685cf634 100644
--- a/apollo-router/src/configuration/mod.rs
+++ b/apollo-router/src/configuration/mod.rs
@@ -707,6 +707,11 @@ pub(crate) struct Supergraph {
     ///
     /// Default is 100.
     pub(crate) experimental_http1_max_headers: Option<usize>,
+
+    /// Set the maximum buffer size for the HTTP1 connection.
+    ///
+    /// Default is ~400kb.
+    pub(crate) experimental_http1_max_buf_size: Option<usize>,
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Deserialize, Serialize, JsonSchema)]
@@ -746,6 +751,7 @@ impl Supergraph {
         early_cancel: Option<bool>,
         experimental_log_on_broken_pipe: Option<bool>,
         experimental_http1_max_headers: Option<usize>,
+        experimental_http1_max_buf_size: Option<usize>,
     ) -> Self {
         Self {
             listen: listen.unwrap_or_else(default_graphql_listen),
@@ -766,6 +772,7 @@ impl Supergraph {
             early_cancel: early_cancel.unwrap_or_default(),
             experimental_log_on_broken_pipe: experimental_log_on_broken_pipe.unwrap_or_default(),
             experimental_http1_max_headers,
+            experimental_http1_max_buf_size,
         }
     }
 }
@@ -785,6 +792,7 @@ impl Supergraph {
         early_cancel: Option<bool>,
         experimental_log_on_broken_pipe: Option<bool>,
         experimental_http1_max_headers: Option<usize>,
+        experimental_http1_max_buf_size: Option<usize>,
     ) -> Self {
         Self {
             listen: listen.unwrap_or_else(test_listen),
@@ -805,6 +813,7 @@ impl Supergraph {
             early_cancel: early_cancel.unwrap_or_default(),
             experimental_log_on_broken_pipe: experimental_log_on_broken_pipe.unwrap_or_default(),
             experimental_http1_max_headers,
+            experimental_http1_max_buf_size,
         }
     }
 }
diff --git a/apollo-router/tests/integration/supergraph.rs b/apollo-router/tests/integration/supergraph.rs
index 8dc48a16dc..bd1672c44a 100644
--- a/apollo-router/tests/integration/supergraph.rs
+++ b/apollo-router/tests/integration/supergraph.rs
@@ -62,3 +62,59 @@ async fn test_supergraph_allow_to_change_http1_max_headers() -> Result<(), BoxEr
     );
     Ok(())
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn test_supergraph_allow_to_change_http1_max_buf_size(
+) -> Result<(), BoxError> {
+    let mut router = IntegrationTest::builder()
+        .config(
+            r#"
+            supergraph:
+              experimental_http1_max_buf_size: 1000000
+            "#,
+        )
+        .build()
+        .await;
+
+    router.start().await;
+    router.assert_started().await;
+
+    let mut headers = HashMap::new();
+    headers.insert(format!("test-header"), "x".repeat(1048576 + 1));
+
+    let (_trace_id, response) = router
+        .execute_query_with_headers(&json!({ "query":  "{ __typename }"}), headers)
+        .await;
+    assert_eq!(response.status(), 431);
+    Ok(())
+}
+
+#[tokio::test(flavor = "multi_thread")]
+async fn test_supergraph_errors_on_http1_header_that_does_not_fit_inside_buffer(
+) -> Result<(), BoxError> {
+    let mut router = IntegrationTest::builder()
+        .config(
+            r#"
+            supergraph:
+              experimental_http1_max_buf_size: 2000000
+            "#,
+        )
+        .build()
+        .await;
+
+    router.start().await;
+    router.assert_started().await;
+
+    let mut headers = HashMap::new();
+    headers.insert(format!("test-header"), "x".repeat(1048576 + 1));
+
+    let (_trace_id, response) = router
+        .execute_query_with_headers(&json!({ "query":  "{ __typename }"}), headers)
+        .await;
+    assert_eq!(response.status(), 200);
+    assert_eq!(
+        response.json::<serde_json::Value>().await?,
+        json!({ "data": { "__typename": "Query" } })
+    );
+    Ok(())
+}