diff --git a/src/testdir/test_vim9_func.vim b/src/testdir/test_vim9_func.vim
index 3d1ae26..c8b821e 100644
--- a/src/testdir/test_vim9_func.vim
+++ b/src/testdir/test_vim9_func.vim
@@ -1052,6 +1052,20 @@
   CheckScriptFailure(['vim9script'] + lines, 'E118: Too many arguments for function: <lambda>', 2)
 enddef
 
+def Test_lambda_line_nr()
+  var lines =<< trim END
+      vim9script
+      # comment
+      # comment
+      var id = timer_start(1'000, (_) => 0)
+      var out = execute('verbose ' .. timer_info(id)[0].callback
+          ->string()
+          ->substitute("('\\|')", ' ', 'g'))
+      assert_match('Last set from .* line 4', out)
+  END
+  CheckScriptSuccess(lines)
+enddef
+
 def FilterWithCond(x: string, Cond: func(string): bool): bool
   return Cond(x)
 enddef
diff --git a/src/userfunc.c b/src/userfunc.c
index 2f0637e..95d9c4a 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -1491,7 +1491,7 @@
 	fp->uf_flags = flags;
 	fp->uf_calls = 0;
 	fp->uf_script_ctx = current_sctx;
-	fp->uf_script_ctx.sc_lnum += SOURCING_LNUM - newlines.ga_len;
+	fp->uf_script_ctx.sc_lnum += SOURCING_LNUM - newlines.ga_len + 1;
 
 	function_using_block_scopes(fp, evalarg->eval_cstack);
 
diff --git a/src/version.c b/src/version.c
index 8eca087..b53524f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3633,
+/**/
     3632,
 /**/
     3631,