diff --git a/lib/core/base/audit.js b/lib/core/base/audit.js
index 5d4dd92b4f..389d77183e 100644
--- a/lib/core/base/audit.js
+++ b/lib/core/base/audit.js
@@ -604,9 +604,7 @@ Audit.prototype.normalizeOptions = function(options) {
 			}, only.values);
 
 			if (unmatchedTags.length !== 0) {
-				throw new Error(
-					'Could not find tags `' + unmatchedTags.join('`, `') + '`'
-				);
+				axe.log('Could not find tags `' + unmatchedTags.join('`, `') + '`');
 			}
 		} else {
 			throw new Error(`Unknown runOnly type '${only.type}'`);
diff --git a/test/core/base/audit.js b/test/core/base/audit.js
index a531315aa2..405d85340b 100644
--- a/test/core/base/audit.js
+++ b/test/core/base/audit.js
@@ -1273,8 +1273,8 @@ describe('Audit', function() {
 			});
 		});
 
-		it('throws an error when option.runOnly has an unknown tag', function() {
-			assert.throws(function() {
+		it("doesn't throw an error when option.runOnly has an unknown tag", function() {
+			assert.doesNotThrow(function() {
 				a.normalizeOptions({
 					runOnly: {
 						type: 'tags',