diff --git a/packages/@aws-cdk/region-info/lib/default.ts b/packages/@aws-cdk/region-info/lib/default.ts
index abd1001678bf2..c0ae0cc2b28d5 100644
--- a/packages/@aws-cdk/region-info/lib/default.ts
+++ b/packages/@aws-cdk/region-info/lib/default.ts
@@ -82,6 +82,7 @@ export class Default {
 
       // Services with a regional principal
       case 'states':
+      case 'ssm':
         return `${service}.${region}.amazonaws.com`;
 
       // Services with a partitional principal
diff --git a/packages/@aws-cdk/region-info/test/default.test.ts b/packages/@aws-cdk/region-info/test/default.test.ts
index b39952842d75a..1e7c1b166c9b6 100644
--- a/packages/@aws-cdk/region-info/test/default.test.ts
+++ b/packages/@aws-cdk/region-info/test/default.test.ts
@@ -5,7 +5,7 @@ const urlSuffix = '.nowhere.null';
 
 describe('servicePrincipal', () => {
   for (const suffix of ['', '.amazonaws.com', '.amazonaws.com.cn']) {
-    for (const service of ['states']) {
+    for (const service of ['states', 'ssm']) {
       test(`${service}${suffix}`, () => {
         expect(Default.servicePrincipal(`${service}${suffix}`, region, urlSuffix)).toBe(`${service}.${region}.amazonaws.com`);
       });