diff --git a/changelog_unreleased/scss/pr-9710.md b/changelog_unreleased/scss/pr-9710.md
new file mode 100644
index 000000000..ca92c1a21
--- /dev/null
+++ b/changelog_unreleased/scss/pr-9710.md
@@ -0,0 +1,23 @@
+#### Fix broken comment inside parens (#9710 by @fisker)
+
+<!-- prettier-ignore -->
+```scss
+// Input
+.simplification {
+  foo: (
+    calc() // not a comment anymore
+  );
+}
+
+// Prettier stable
+.simplification {
+  foo: (calc() // not a comment anymore);
+}
+
+// Prettier master
+.simplification {
+  foo: (
+    calc() // not a comment anymore
+  );
+}
+```
diff --git a/src/language-css/printer-postcss.js b/src/language-css/printer-postcss.js
index 74b5ec151..bbbf0c3e6 100644
--- a/src/language-css/printer-postcss.js
+++ b/src/language-css/printer-postcss.js
@@ -534,6 +534,9 @@ function genericPrint(path, options, print) {
       const atRuleAncestorNode = getAncestorNode(path, "css-atrule");
       const isControlDirective =
         atRuleAncestorNode && isSCSSControlDirectiveNode(atRuleAncestorNode);
+      const hasInlineComment = node.groups.some((node) =>
+        isInlineValueCommentNode(node)
+      );
 
       const printed = path.map(print, "groups");
       const parts = [];
@@ -800,6 +803,10 @@ function genericPrint(path, options, print) {
         parts.push(line);
       }
 
+      if (hasInlineComment) {
+        parts.push(breakParent);
+      }
+
       if (didBreak) {
         parts.unshift(hardline);
       }
diff --git a/tests/less/comments/__snapshots__/jsfmt.spec.js.snap b/tests/less/comments/__snapshots__/jsfmt.spec.js.snap
index ba0123c2a..d34539e2b 100644
--- a/tests/less/comments/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/less/comments/__snapshots__/jsfmt.spec.js.snap
@@ -198,6 +198,46 @@ printWidth: 80
 ================================================================================
 `;
 
+exports[`in-value.less format 1`] = `
+====================================options=====================================
+parsers: ["less"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+.real-world-example {
+  background: radial-gradient(
+      circle at left 0% bottom $position,
+      transparent,
+      transparent $diameter,
+      #fbfbfb calc(#{$diameter} + 1px) // Add 1px for edge-smoothing.
+    );
+}
+
+.simplification { 
+  foo: (
+    calc() // not a comment anymore
+  );
+}
+
+=====================================output=====================================
+.real-world-example {
+  background: radial-gradient(
+    circle at left 0% bottom $position,
+    transparent,
+    transparent $diameter,
+    #fbfbfb calc(#{$diameter} + 1px) // Add 1px for edge-smoothing.
+  );
+}
+
+.simplification {
+  foo: (
+    calc() // not a comment anymore
+  );
+}
+
+================================================================================
+`;
+
 exports[`issue-8130.less format 1`] = `
 ====================================options=====================================
 parsers: ["less"]
diff --git a/tests/less/comments/in-value.less b/tests/less/comments/in-value.less
new file mode 100644
index 000000000..4729f124e
--- /dev/null
+++ b/tests/less/comments/in-value.less
@@ -0,0 +1,14 @@
+.real-world-example {
+  background: radial-gradient(
+      circle at left 0% bottom $position,
+      transparent,
+      transparent $diameter,
+      #fbfbfb calc(#{$diameter} + 1px) // Add 1px for edge-smoothing.
+    );
+}
+
+.simplification { 
+  foo: (
+    calc() // not a comment anymore
+  );
+}
diff --git a/tests/scss/comments/__snapshots__/jsfmt.spec.js.snap b/tests/scss/comments/__snapshots__/jsfmt.spec.js.snap
index d6d360762..45cf082b4 100644
--- a/tests/scss/comments/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/scss/comments/__snapshots__/jsfmt.spec.js.snap
@@ -338,6 +338,46 @@ printWidth: 80
 ================================================================================
 `;
 
+exports[`in-value.scss format 1`] = `
+====================================options=====================================
+parsers: ["scss"]
+printWidth: 80
+                                                                                | printWidth
+=====================================input======================================
+.real-world-example {
+  background: radial-gradient(
+      circle at left 0% bottom $position,
+      transparent,
+      transparent $diameter,
+      #fbfbfb calc(#{$diameter} + 1px) // Add 1px for edge-smoothing.
+    );
+}
+
+.simplification { 
+  foo: (
+    calc() // not a comment anymore
+  );
+}
+
+=====================================output=====================================
+.real-world-example {
+  background: radial-gradient(
+    circle at left 0% bottom $position,
+    transparent,
+    transparent $diameter,
+    #fbfbfb calc(#{$diameter} + 1px) // Add 1px for edge-smoothing.
+  );
+}
+
+.simplification {
+  foo: (
+    calc() // not a comment anymore
+  );
+}
+
+================================================================================
+`;
+
 exports[`lists.scss format 1`] = `
 ====================================options=====================================
 parsers: ["scss"]
diff --git a/tests/scss/comments/in-value.scss b/tests/scss/comments/in-value.scss
new file mode 100644
index 000000000..4729f124e
--- /dev/null
+++ b/tests/scss/comments/in-value.scss
@@ -0,0 +1,14 @@
+.real-world-example {
+  background: radial-gradient(
+      circle at left 0% bottom $position,
+      transparent,
+      transparent $diameter,
+      #fbfbfb calc(#{$diameter} + 1px) // Add 1px for edge-smoothing.
+    );
+}
+
+.simplification { 
+  foo: (
+    calc() // not a comment anymore
+  );
+}