diff --git a/packages/functions/src/__tests__/xor.test.ts b/packages/functions/src/__tests__/xor.test.ts
index 6ea29e233..49d328f32 100644
--- a/packages/functions/src/__tests__/xor.test.ts
+++ b/packages/functions/src/__tests__/xor.test.ts
@@ -26,6 +26,24 @@ describe('Core Functions / Xor', () => {
     ]);
   });
 
+  it('given multiple properties that do not match, should return an error message', async () => {
+    expect(
+      await runXor(
+        {
+          version: '1.0.0',
+          title: 'Swagger Petstore',
+          termsOfService: 'http://swagger.io/terms/',
+        },
+        { properties: ['yada-yada', 'whatever', 'foo'] },
+      ),
+    ).toEqual([
+      {
+        message: '"yada-yada", "whatever" and "foo" must not be both defined or both undefined',
+        path: [],
+      },
+    ]);
+  });
+
   it('given both properties, should return an error message', async () => {
     expect(
       await runXor(
@@ -99,22 +117,12 @@ describe('Core Functions / Xor', () => {
           ]),
         ],
       ],
-      [
-        { properties: ['foo', 'bar', 'baz'] },
-        [
-          new RulesetValidationError(
-            'invalid-function-options',
-            '"xor" and its "properties" option support 2-item tuples, i.e. ["id", "name"]',
-            ['rules', 'my-rule', 'then', 'functionOptions', 'properties'],
-          ),
-        ],
-      ],
       [
         { properties: ['foo', {}] },
         [
           new RulesetValidationError(
             'invalid-function-options',
-            '"xor" and its "properties" option support 2-item tuples, i.e. ["id", "name"]',
+            '"xor" and its "properties" option require at least 2-item tuples, i.e. ["id", "name"]',
             ['rules', 'my-rule', 'then', 'functionOptions', 'properties'],
           ),
         ],
@@ -124,7 +132,7 @@ describe('Core Functions / Xor', () => {
         [
           new RulesetValidationError(
             'invalid-function-options',
-            '"xor" and its "properties" option support 2-item tuples, i.e. ["id", "name"]',
+            '"xor" and its "properties" option require at least 2-item tuples, i.e. ["id", "name"]',
             ['rules', 'my-rule', 'then', 'functionOptions', 'properties'],
           ),
         ],
@@ -134,7 +142,7 @@ describe('Core Functions / Xor', () => {
         [
           new RulesetValidationError(
             'invalid-function-options',
-            '"xor" and its "properties" option support 2-item tuples, i.e. ["id", "name"]',
+            '"xor" and its "properties" option require at least 2-item tuples, i.e. ["id", "name"]',
             ['rules', 'my-rule', 'then', 'functionOptions', 'properties'],
           ),
         ],
diff --git a/packages/functions/src/optionSchemas.ts b/packages/functions/src/optionSchemas.ts
index f9a93c15e..7a3a2741d 100644
--- a/packages/functions/src/optionSchemas.ts
+++ b/packages/functions/src/optionSchemas.ts
@@ -207,8 +207,7 @@ export const optionSchemas: Record<string, CustomFunctionOptionsSchema> = {
           type: 'string',
         },
         minItems: 2,
-        maxItems: 2,
-        errorMessage: `"xor" and its "properties" option support 2-item tuples, i.e. ["id", "name"]`,
+        errorMessage: `"xor" and its "properties" option require at least 2-item tuples, i.e. ["id", "name"]`,
         description: 'The properties to check.',
       },
     },
diff --git a/packages/functions/src/xor.ts b/packages/functions/src/xor.ts
index e9a122251..5d5d68b78 100644
--- a/packages/functions/src/xor.ts
+++ b/packages/functions/src/xor.ts
@@ -16,16 +16,20 @@ export default createRulesetFunction<Record<string, unknown>, Options>(
     options: optionSchemas.xor,
   },
   function xor(targetVal, { properties }) {
-    if (properties.length !== 2) return;
-
     const results: IFunctionResult[] = [];
 
-    const intersection = Object.keys(targetVal).filter(value => -1 !== properties.indexOf(value));
+    const intersection = Object.keys(targetVal).filter(key => properties.includes(key));
+
     if (intersection.length !== 1) {
+      const formattedProperties = properties.map(prop => printValue(prop));
+
+      const lastProperty = formattedProperties.pop();
+      let message = formattedProperties.join(', ') + (lastProperty != undefined ? ` and ${lastProperty}` : '');
+
+      message += ' must not be both defined or both undefined';
+
       results.push({
-        message: `${printValue(properties[0])} and ${printValue(
-          properties[1],
-        )} must not be both defined or both undefined`,
+        message,
       });
     }