diff --git a/src/language-css/printer-postcss.js b/src/language-css/printer-postcss.js
index b6b26562f597..a8535654fb7e 100644
--- a/src/language-css/printer-postcss.js
+++ b/src/language-css/printer-postcss.js
@@ -647,7 +647,11 @@ function genericPrint(path, options, print) {
 
         // Formatting `grid` property
         if (isGridValue) {
-          if (iNode.source.start.line !== iNextNode.source.start.line) {
+          if (
+            iNode.source &&
+            iNextNode.source &&
+            iNode.source.start.line !== iNextNode.source.start.line
+          ) {
             parts.push(hardline);
 
             didBreak = true;
diff --git a/tests/css_scss/__snapshots__/jsfmt.spec.js.snap b/tests/css_scss/__snapshots__/jsfmt.spec.js.snap
index 606119189141..2c32af285148 100644
--- a/tests/css_scss/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/css_scss/__snapshots__/jsfmt.spec.js.snap
@@ -1044,6 +1044,10 @@ $my-map: (
     color: $color-silver;
   }
 }
+
+.something {
+  grid-template-columns: 1 2fr (3 + 4);
+}
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 @media #{$g-breakpoint-tiny} {
 }
@@ -1994,4 +1998,8 @@ $my-map: (
   }
 }
 
+.something {
+  grid-template-columns: 1 2fr (3 + 4);
+}
+
 `;
diff --git a/tests/css_scss/scss.scss b/tests/css_scss/scss.scss
index c74da6503c38..849a02a6a5f1 100644
--- a/tests/css_scss/scss.scss
+++ b/tests/css_scss/scss.scss
@@ -1034,3 +1034,7 @@ $my-map: (
     color: $color-silver;
   }
 }
+
+.something {
+  grid-template-columns: 1 2fr (3 + 4);
+}