diff --git a/.changeset/grumpy-melons-grow.md b/.changeset/grumpy-melons-grow.md
new file mode 100644
index 0000000000..dfd599d0ca
--- /dev/null
+++ b/.changeset/grumpy-melons-grow.md
@@ -0,0 +1,5 @@
+---
+"viem": patch
+---
+
+Fixed an issue where \`hashAuthorization\` & \`serializeAuthorizationList\` did not RLP-serialize zeroish nonces correctly.
diff --git a/src/actions/wallet/sendTransaction.test.ts b/src/actions/wallet/sendTransaction.test.ts
index 96e062bc35..b73c495772 100644
--- a/src/actions/wallet/sendTransaction.test.ts
+++ b/src/actions/wallet/sendTransaction.test.ts
@@ -10,6 +10,7 @@ import { maxUint256 } from '~viem/constants/number.js'
 import { BatchCallInvoker } from '../../../contracts/generated.js'
 import { getSmartAccounts_07 } from '../../../test/src/account-abstraction.js'
 import { deploy } from '../../../test/src/utils.js'
+import { generatePrivateKey } from '../../accounts/generatePrivateKey.js'
 import { createWalletClient } from '../../clients/createWalletClient.js'
 import { http } from '../../clients/transports/http.js'
 import { signAuthorization } from '../../experimental/index.js'
@@ -1406,3 +1407,48 @@ describe('errors', () => {
     )
   })
 })
+
+test('https://github.com/wevm/viem/issues/2721', async () => {
+  const invoker = privateKeyToAccount(generatePrivateKey())
+  const authority = privateKeyToAccount(generatePrivateKey())
+  const recipient = privateKeyToAccount(generatePrivateKey())
+
+  await setBalance(client, {
+    address: invoker.address,
+    value: parseEther('100'),
+  })
+  await setBalance(client, {
+    address: authority.address,
+    value: parseEther('100'),
+  })
+
+  const { contractAddress } = await deploy(client, {
+    abi: BatchCallInvoker.abi,
+    bytecode: BatchCallInvoker.bytecode.object,
+  })
+
+  const authorization = await signAuthorization(client, {
+    account: authority,
+    contractAddress: contractAddress!,
+  })
+
+  const hash = await sendTransaction(client, {
+    account: invoker,
+    authorizationList: [authorization],
+    data: encodeFunctionData({
+      abi: BatchCallInvoker.abi,
+      functionName: 'execute',
+      args: [
+        [
+          {
+            to: recipient.address,
+            data: '0x',
+            value: parseEther('1'),
+          },
+        ],
+      ],
+    }),
+    to: authority.address,
+  })
+  expect(hash).toBeDefined()
+})
diff --git a/src/experimental/eip7702/utils/hashAuthorization.ts b/src/experimental/eip7702/utils/hashAuthorization.ts
index 6b544a3fbd..9a6773ab66 100644
--- a/src/experimental/eip7702/utils/hashAuthorization.ts
+++ b/src/experimental/eip7702/utils/hashAuthorization.ts
@@ -48,7 +48,11 @@ export function hashAuthorization<to extends To = 'hex'>(
   const hash = keccak256(
     concatHex([
       '0x05',
-      toRlp([numberToHex(chainId), contractAddress, numberToHex(nonce)]),
+      toRlp([
+        numberToHex(chainId),
+        contractAddress,
+        nonce ? numberToHex(nonce) : '0x',
+      ]),
     ]),
   )
   if (to === 'bytes') return hexToBytes(hash) as HashAuthorizationReturnType<to>
diff --git a/src/experimental/eip7702/utils/serializeAuthorizationList.ts b/src/experimental/eip7702/utils/serializeAuthorizationList.ts
index 99d2fcd007..71df1faa72 100644
--- a/src/experimental/eip7702/utils/serializeAuthorizationList.ts
+++ b/src/experimental/eip7702/utils/serializeAuthorizationList.ts
@@ -24,7 +24,7 @@ export function serializeAuthorizationList(
     serializedAuthorizationList.push([
       toHex(chainId),
       contractAddress,
-      toHex(nonce),
+      nonce ? toHex(nonce) : '0x',
       ...toYParitySignatureArray({}, signature),
     ])
   }