diff --git a/verilog-align-ports.el b/verilog-align-ports.el
index 4681b8c..0e248e2 100644
--- a/verilog-align-ports.el
+++ b/verilog-align-ports.el
@@ -67,24 +67,23 @@
 
 (defun verilog-align-ports--bounds ()
   (save-excursion
-    (unless (verilog-align-ports--line-port-p (line-beginning-position))
-      (user-error "Point is not on a port declaration line"))
-    (let ((start (line-beginning-position))
-          (end nil))
-      (while (and (not (bobp))
-                  (save-excursion
-                    (forward-line -1)
-                    (verilog-align-ports--line-port-p
-                     (line-beginning-position))))
-        (forward-line -1)
-        (setq start (line-beginning-position)))
-      (goto-char start)
-      (while (and (not (eobp))
-                  (verilog-align-ports--line-port-p
-                   (line-beginning-position)))
-        (forward-line 1))
-      (setq end (line-beginning-position))
-      (cons start end))))
+    (and (verilog-align-ports--line-port-p (line-beginning-position))
+         (let ((start (line-beginning-position))
+               (end nil))
+           (while (and (not (bobp))
+                       (save-excursion
+                         (forward-line -1)
+                         (verilog-align-ports--line-port-p
+                          (line-beginning-position))))
+             (forward-line -1)
+             (setq start (line-beginning-position)))
+           (goto-char start)
+           (while (and (not (eobp))
+                       (verilog-align-ports--line-port-p
+                        (line-beginning-position)))
+             (forward-line 1))
+           (setq end (line-beginning-position))
+           (cons start end)))))
 
 (defun verilog-align-ports--collect (start end)
   (let (entries)
@@ -169,14 +168,15 @@
 (defun verilog-align-ports ()
   "Align SystemVerilog port declarations around point."
   (interactive)
-  (let* ((bounds (verilog-align-ports--bounds))
-         (start (car bounds))
-         (end (cdr bounds))
-         (entries (verilog-align-ports--collect start end)))
-    (when (null entries)
-      (user-error "No port declarations found"))
-    (let ((lines (verilog-align-ports--format-lines entries)))
-      (verilog-align-ports--apply start lines))))
+  (let ((bounds (verilog-align-ports--bounds)))
+    (and bounds
+         (let* ((start (car bounds))
+                (end (cdr bounds))
+                (entries (verilog-align-ports--collect start end)))
+           (and entries
+                (let ((lines (verilog-align-ports--format-lines entries)))
+                  (verilog-align-ports--apply start lines)
+                  t))))))
 
 (provide 'verilog-align-ports)