diff --git a/emacs/notmuch-lib.el b/emacs/notmuch-lib.el
index 546ab6fd..7fc342a5 100644
--- a/emacs/notmuch-lib.el
+++ b/emacs/notmuch-lib.el
@@ -1008,6 +1008,15 @@ status."
 (defvar notmuch-show-process-crypto nil)
 (make-variable-buffer-local 'notmuch-show-process-crypto)
 
+(defun notmuch-interactive-region ()
+  "Return the bounds of the current interactive region.
+
+This returns (BEG END), where BEG and END are the bounds of the
+region if the region is active, or both `point' otherwise."
+  (if (region-active-p)
+      (list (region-beginning) (region-end))
+    (list (point) (point))))
+
 (provide 'notmuch-lib)
 
 ;; Local Variables:
diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index 804e78ab..773d1206 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -557,20 +557,11 @@ thread."
 	(setq output (append output (notmuch-search-get-tags pos)))))
     output))
 
-(defun notmuch-search-interactive-region ()
-  "Return the bounds of the current interactive region.
-
-This returns (BEG END), where BEG and END are the bounds of the
-region if the region is active, or both `point' otherwise."
-  (if (region-active-p)
-      (list (region-beginning) (region-end))
-    (list (point) (point))))
-
 (defun notmuch-search-interactive-tag-changes (&optional initial-input)
   "Prompt for tag changes for the current thread or region.
 
 Returns (TAG-CHANGES REGION-BEGIN REGION-END)."
-  (let* ((region (notmuch-search-interactive-region))
+  (let* ((region (notmuch-interactive-region))
 	 (beg (first region)) (end (second region))
 	 (prompt (if (= beg end) "Tag thread" "Tag region")))
     (cons (notmuch-read-tag-changes
@@ -590,8 +581,8 @@ is inactive this applies to the thread at point.
 If ONLY-MATCHED is non-nil, only tag matched messages."
   (interactive (notmuch-search-interactive-tag-changes))
   (unless (and beg end)
-    (setq beg (car (notmuch-search-interactive-region))
-	  end (cadr (notmuch-search-interactive-region))))
+    (setq beg (car (notmuch-interactive-region))
+	  end (cadr (notmuch-interactive-region))))
   (let ((search-string (notmuch-search-find-stable-query-region
 			beg end only-matched)))
     (notmuch-tag search-string tag-changes)
@@ -627,7 +618,7 @@ messages will be \"unarchived\" (i.e. the tag changes in
 `notmuch-archive-tags' will be reversed).
 
 This function advances the next thread when finished."
-  (interactive (cons current-prefix-arg (notmuch-search-interactive-region)))
+  (interactive (cons current-prefix-arg (notmuch-interactive-region)))
   (when notmuch-archive-tags
     (notmuch-search-tag
      (notmuch-tag-change-list notmuch-archive-tags unarchive) beg end))