diff --git a/package.json b/package.json
index b6f84c4bf6..418a72681a 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
   },
   "devDependencies": {
     "@babel/core": "^7.2.2",
-    "@polkadot/dev": "^0.23.10",
+    "@polkadot/dev": "^0.23.11",
     "@polkadot/ts": "^0.1.50"
   }
 }
diff --git a/packages/types/src/AccountId.spec.ts b/packages/types/src/AccountId.spec.ts
index fd1be01ba0..1223605329 100644
--- a/packages/types/src/AccountId.spec.ts
+++ b/packages/types/src/AccountId.spec.ts
@@ -43,9 +43,9 @@ describe('AccountId', () => {
   });
 
   describe('encoding', () => {
-    const testEncode = (to: 'toHex' | 'toJSON' | 'toString' | 'toU8a', expected: Uint8Array | string) =>
+    const testEncode = (to: 'toHex' | 'toJSON' | 'toString' | 'toU8a', expected: Uint8Array | string, input: string = '5C62W7ELLAAfix9LYrcx5smtcffbhvThkM5x7xfMeYXCt72s') =>
       it(`can encode ${to}`, () => {
-        const a = new AccountId('5C62W7ELLAAfix9LYrcx5smtcffbhvThkM5x7xfMeYXCt72s');
+        const a = new AccountId(input);
 
         expect(a[to]()).toEqual(expected);
       });
@@ -53,6 +53,7 @@ describe('AccountId', () => {
     testEncode('toHex', '0x0102030405060708010203040506070801020304050607080102030405060708');
     testEncode('toJSON', '5C62W7ELLAAfix9LYrcx5smtcffbhvThkM5x7xfMeYXCt72s');
     testEncode('toString', '5C62W7ELLAAfix9LYrcx5smtcffbhvThkM5x7xfMeYXCt72s');
+    testEncode('toString', '-', '0x00');
     testEncode('toU8a', Uint8Array.from([
       1, 2, 3, 4, 5, 6, 7, 8, 1, 2, 3, 4, 5, 6, 7, 8,
       1, 2, 3, 4, 5, 6, 7, 8, 1, 2, 3, 4, 5, 6, 7, 8
diff --git a/packages/types/src/AccountId.ts b/packages/types/src/AccountId.ts
index a7247a55da..1898d4448b 100644
--- a/packages/types/src/AccountId.ts
+++ b/packages/types/src/AccountId.ts
@@ -41,9 +41,16 @@ export default class AccountId extends U8aFixed {
   }
 
   /**
-   * @description Returns true if the type wraps a non-encodable value
+   * @description Returns true if the type wraps an empty value
    */
   get isEmpty (): boolean {
+    return this.length === 1 && this[0] === 0;
+  }
+
+  /**
+   * @description Returns true if the type wraps a non-valid value
+   */
+  get isInvalid (): boolean {
     return this.length !== 32;
   }
 
@@ -58,6 +65,8 @@ export default class AccountId extends U8aFixed {
    * @description Returns the string representation of the value
    */
   toString (): string {
-    return AccountId.encode(this);
+    return this.isEmpty
+      ? '-'
+      : AccountId.encode(this);
   }
 }
diff --git a/yarn.lock b/yarn.lock
index b7f6ec08dc..ffc8158275 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1293,10 +1293,10 @@
   resolved "https://registry.yarnpkg.com/@nodelib/fs.stat/-/fs.stat-1.1.3.tgz#2b5a3ab3f918cca48a8c754c08168e3f03eba61b"
   integrity sha512-shAmDyaQC4H92APFoIaVDHCx5bStIocgvbwQyxPRrbUY20V1EYTbSDchWbuwlMG3V17cprZhA6+78JfB+3DTPw==
 
-"@polkadot/dev@^0.23.10":
-  version "0.23.10"
-  resolved "https://registry.yarnpkg.com/@polkadot/dev/-/dev-0.23.10.tgz#ab76f12475fd3149cdab819174d5395da33f16d4"
-  integrity sha512-W9l9IygZnWnvm6hjdjY9IWbnrxiZSpFlRKD7bnA4PRKA326TbmtUFye4XOBoNVAA5+W2gGZd8UyGjs0ezfDCaA==
+"@polkadot/dev@^0.23.11":
+  version "0.23.11"
+  resolved "https://registry.yarnpkg.com/@polkadot/dev/-/dev-0.23.11.tgz#0b8d31553037b17113e29ead710117192880aac0"
+  integrity sha512-C8GIU06+yXW5Gc3K4jntLYI97JgCO/Hr7JRGFUYwjuPGmluBVkFS+b8/QaIHEwUCTGBk53FawKQqX9ABEXK14A==
   dependencies:
     "@babel/cli" "^7.2.3"
     "@babel/core" "^7.2.2"