diff --git a/src/edit.c b/src/edit.c
index ee3caf0..2b53011 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -4452,7 +4452,8 @@
 		    break;
 
 		case PASTE_EX:
-		    if (gap != NULL && ga_grow(gap, idx) == OK)
+		    // add one for the NUL that is going to be appended
+		    if (gap != NULL && ga_grow(gap, idx + 1) == OK)
 		    {
 			mch_memmove((char *)gap->ga_data + gap->ga_len,
 							     buf, (size_t)idx);
diff --git a/src/testdir/test_paste.vim b/src/testdir/test_paste.vim
index c94fe7c..5b8d8a0 100644
--- a/src/testdir/test_paste.vim
+++ b/src/testdir/test_paste.vim
@@ -90,6 +90,9 @@
   unlet! foo
   call feedkeys("Qlet foo=\"\<Esc>[200~foo\<CR>bar\<Esc>[201~\"\<CR>vi\<CR>", 'xt')
   call assert_equal("foo\rbar", foo)
+
+  " pasting more than 40 bytes
+  exe "norm Q\<PasteStart>0000000000000000000000000000000000000000000000000000000000000000000000\<C-C>"
 endfunc
 
 func Test_paste_onechar()
diff --git a/src/version.c b/src/version.c
index 6685b55..9dcf349 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4218,
+/**/
     4217,
 /**/
     4216,