diff --git a/server/src/lib/score-import/framework/calculated-data/calculated-data.test.ts b/server/src/lib/score-import/framework/calculated-data/calculated-data.test.ts
index 076d9502a..da2e88425 100644
--- a/server/src/lib/score-import/framework/calculated-data/calculated-data.test.ts
+++ b/server/src/lib/score-import/framework/calculated-data/calculated-data.test.ts
@@ -10,6 +10,7 @@ import {
 	TestingSDVXSingleDryScore,
 } from "test-utils/test-data";
 import { CreateCalculatedData, CalculateDataForGamePT } from "./calculated-data";
+import { ChartDocument, ScoreDocument } from "tachi-common";
 
 const logger = CreateLogCtx(__filename);
 
@@ -41,6 +42,15 @@ t.test("#CreateCalculatedData", async (t) => {
 		"Should correctly call rating function overrides for different games"
 	);
 
+	const uscRes = await CreateCalculatedData(
+		{ game: "usc", playtype: "Single" } as ScoreDocument,
+		{ data: { isOfficial: false }, playtype: "Single" } as ChartDocument,
+		null,
+		logger
+	);
+
+	t.strictSame(uscRes, { VF6: null }, "Should return null if chart was not an official.");
+
 	t.end();
 });
 
diff --git a/server/src/lib/score-import/framework/calculated-data/calculated-data.ts b/server/src/lib/score-import/framework/calculated-data/calculated-data.ts
index 2ffdb58be..c4d49f099 100644
--- a/server/src/lib/score-import/framework/calculated-data/calculated-data.ts
+++ b/server/src/lib/score-import/framework/calculated-data/calculated-data.ts
@@ -199,6 +199,11 @@ function CalculateDataSDVXorUSC(
 	defaultTierlistID: string | undefined,
 	logger: KtLogger
 ): CalculatedData<"sdvx:Single" | "usc:Single"> {
+	// for usc, unofficial charts currently have no VF6 value.
+	if (dryScore.game === "usc" && !(chart as ChartDocument<"usc:Single">).data.isOfficial) {
+		return { VF6: null };
+	}
+
 	const VF6 = CalculateVF6(
 		dryScore.scoreData.grade as Grades["sdvx:Single"],
 		dryScore.scoreData.lamp as Lamps["sdvx:Single"],