diff --git a/components/esp_http_server/include/esp_http_server.h b/components/esp_http_server/include/esp_http_server.h
index 1ca768ae257..cd3299cdb37 100644
--- a/components/esp_http_server/include/esp_http_server.h
+++ b/components/esp_http_server/include/esp_http_server.h
@@ -380,7 +380,7 @@ esp_err_t httpd_stop(httpd_handle_t handle);
  */
 typedef struct httpd_req {
     httpd_handle_t  handle;                     /*!< Handle to server instance */
-    int             method;                     /*!< The type of HTTP request, -1 if unsupported method, HTTP_ANY for wildcard method to support every method */
+    int             method;                     /*!< The type of HTTP request (enum http_method); a request with an unrecognized method is rejected with 501 before any URI handler runs */
     const char      uri[CONFIG_HTTPD_MAX_URI_LEN + 1]; /*!< The URI of this request (1 byte extra for null termination) */
     size_t          content_len;                /*!< Length of the request body */
     void           *aux;                        /*!< Internally used members */
@@ -612,10 +612,11 @@ typedef enum {
      */
     HTTPD_500_INTERNAL_SERVER_ERROR = 0,
 
-    /* For methods not supported by http_parser. Presently
-     * http_parser halts parsing when such methods are
-     * encountered and so the server responds with 400 Bad
-     * Request error instead.
+    /* For request methods that http_parser does not recognize,
+     * and for requests carrying a Transfer-Encoding header (no
+     * transfer coding is implemented). Parsing aborted mid-request
+     * in both cases, so the server closes the session after the
+     * response regardless of what a custom error handler returns.
      */
     HTTPD_501_METHOD_NOT_IMPLEMENTED,
 
@@ -623,8 +624,8 @@ typedef enum {
     HTTPD_505_VERSION_NOT_SUPPORTED,
 
     /* Returned when http_parser halts parsing due to incorrect
-     * syntax of request, unsupported method in request URI or
-     * due to chunked encoding / upgrade field present in headers
+     * syntax of request or due to an upgrade field present in
+     * headers that the server does not handle
      */
     HTTPD_400_BAD_REQUEST,
 
diff --git a/components/esp_http_server/src/httpd_parse.c b/components/esp_http_server/src/httpd_parse.c
index 8245ae3291a..2f8b2901f0b 100644
--- a/components/esp_http_server/src/httpd_parse.c
+++ b/components/esp_http_server/src/httpd_parse.c
@@ -68,12 +68,10 @@ static esp_err_t verify_url (http_parser *parser)
     const char *at = parser_data->last.at;
     size_t  length = parser_data->last.length;
 
+    /* http_parser stops with HPE_INVALID_METHOD before the URL callback for
+     * any method token it does not know, so the method is always valid here.
+     * That parser error is mapped to 501 in parse_block(). */
     r->method = parser->method;
-    if (r->method < 0) {
-        ESP_LOGW(TAG, LOG_FMT("HTTP method not supported (%d)"), r->method);
-        parser_data->error = HTTPD_501_METHOD_NOT_IMPLEMENTED;
-        return ESP_FAIL;
-    }
 
     if (sizeof(r->uri) < (length + 1)) {
         ESP_LOGW(TAG, LOG_FMT("URI length (%"NEWLIB_NANO_COMPAT_FORMAT") greater than supported (%"NEWLIB_NANO_COMPAT_FORMAT")"),
@@ -600,6 +598,17 @@ static int read_block(httpd_req_t *req, http_parser *parser, size_t offset, size
     return nbytes;
 }
 
+/* Map an http_parser failure to the HTTP status sent back. An unrecognized
+ * request method is a 501 (RFC 9110 section 15.6.2), every other parser
+ * error means the request syntax is malformed. */
+static httpd_err_code_t parser_errno_to_err_code(const http_parser *parser)
+{
+    if (HTTP_PARSER_ERRNO(parser) == HPE_INVALID_METHOD) {
+        return HTTPD_501_METHOD_NOT_IMPLEMENTED;
+    }
+    return HTTPD_400_BAD_REQUEST;
+}
+
 static int parse_block(http_parser *parser, size_t offset, size_t length)
 {
     parser_data_t        *data  = (parser_data_t *)(parser->data);
@@ -661,14 +670,14 @@ static int parse_block(http_parser *parser, size_t offset, size_t length)
         return 0;
     } else if (nparsed != length) {
         /* http_parser error */
-        data->error  = HTTPD_400_BAD_REQUEST;
+        data->error  = parser_errno_to_err_code(parser);
         data->status = PARSING_FAILED;
         ESP_LOGW(TAG, LOG_FMT("incomplete (%"NEWLIB_NANO_COMPAT_FORMAT"/%"NEWLIB_NANO_COMPAT_FORMAT") with parser error = %d"),
                  NEWLIB_NANO_COMPAT_CAST(nparsed), NEWLIB_NANO_COMPAT_CAST(length), parser->http_errno);
         return -1;
     } else if (HTTP_PARSER_ERRNO(parser) != HPE_OK) {
         /* http_parser error */
-        data->error  = HTTPD_400_BAD_REQUEST;
+        data->error  = parser_errno_to_err_code(parser);
         data->status = PARSING_FAILED;
         ESP_LOGE(TAG, LOG_FMT("parser error: %s"), http_errno_description(HTTP_PARSER_ERRNO(parser)));
         return -1;