diff --git a/prdoc/pr_12220.prdoc b/prdoc/pr_12220.prdoc
new file mode 100644
index 0000000000000..6442a6f63809d
--- /dev/null
+++ b/prdoc/pr_12220.prdoc
@@ -0,0 +1,10 @@
+title: 'pallet-revive eth-rpc: make SubmittedTransaction::gas() return Option<U256>'
+doc:
+- audience: Node Dev
+  description: |-
+    closes #11889
+
+    Change `SubmittedTransaction::gas()` to return `Option<U256>` mirroring the underlying `GenericTransaction::gas` field, and skip the `wait_for_receipt` gas-limit assertion when no gas limit is set, removing the panic that occurred on legacy/incomplete payloads.
+crates:
+- name: pallet-revive-eth-rpc
+  bump: major
diff --git a/substrate/frame/revive/rpc/examples/deploy.rs b/substrate/frame/revive/rpc/examples/deploy.rs
index ac3a8ce07d7fb..2c835e3607a6c 100644
--- a/substrate/frame/revive/rpc/examples/deploy.rs
+++ b/substrate/frame/revive/rpc/examples/deploy.rs
@@ -54,7 +54,7 @@ async fn main() -> anyhow::Result<()> {
 
 	println!("Receipt:");
 	println!("- Block number:     {block_number}");
-	println!("- Gas estimated:    {}", tx.gas());
+	println!("- Gas estimated:    {:?}", tx.gas());
 	println!("- Gas used:         {gas_used}");
 	println!("- Contract address: {contract_address:?}");
 	let balance = client.get_balance(contract_address, BlockTag::Latest.into()).await?;
@@ -76,7 +76,7 @@ async fn main() -> anyhow::Result<()> {
 	println!("Receipt:");
 	println!("- Block number:  {block_number}");
 	println!("- Gas used:      {gas_used}");
-	println!("- Gas estimated: {}", tx.gas());
+	println!("- Gas estimated: {:?}", tx.gas());
 	println!("- To:            {to:?}");
 	Ok(())
 }
diff --git a/substrate/frame/revive/rpc/src/example.rs b/substrate/frame/revive/rpc/src/example.rs
index 1ae77e887ec4f..c4b6ee75c81e3 100644
--- a/substrate/frame/revive/rpc/src/example.rs
+++ b/substrate/frame/revive/rpc/src/example.rs
@@ -54,9 +54,12 @@ impl<Client: EthRpcClient + Sync + Send> SubmittedTransaction<Client> {
 		self.hash
 	}
 
-	/// The gas sent with the transaction.
-	pub fn gas(&self) -> U256 {
-		self.tx.gas.unwrap()
+	/// The gas limit sent with the transaction, if one was specified.
+	///
+	/// This mirrors [`GenericTransaction::gas`], which is optional for legacy/incomplete
+	/// payloads, so it can be `None`.
+	pub fn gas(&self) -> Option<U256> {
+		self.tx.gas
 	}
 
 	pub fn generic_transaction(&self) -> GenericTransaction {
@@ -79,12 +82,14 @@ impl<Client: EthRpcClient + Sync + Send> SubmittedTransaction<Client> {
 	pub async fn wait_for_receipt(&self) -> anyhow::Result<ReceiptInfo> {
 		let receipt = self.wait_for_receipt_any().await?;
 		if receipt.is_success() {
-			assert!(
-				self.gas() >= receipt.gas_used,
-				"Gas used {:?} should be less than or equal to gas limit {:?}",
-				receipt.gas_used,
-				self.gas()
-			);
+			if let Some(gas) = self.gas() {
+				assert!(
+					gas >= receipt.gas_used,
+					"Gas used {:?} should be less than or equal to gas limit {:?}",
+					receipt.gas_used,
+					gas
+				);
+			}
 			Ok(receipt)
 		} else {
 			anyhow::bail!("Transaction failed receipt: {receipt:?}")