diff --git a/crates/nox-tests/tests/builtin.rs b/crates/nox-tests/tests/builtin.rs
index f3333a6267..e7ae077f90 100644
--- a/crates/nox-tests/tests/builtin.rs
+++ b/crates/nox-tests/tests/builtin.rs
@@ -2201,7 +2201,7 @@ async fn subnet_resolve() {
         // expect to receive this exact body in POST
         // .match_body(r#"{"jsonrpc":"2.0","id":0,"method":"eth_getLogs","params":[{"fromBlock":"0x52","toBlock":"0x246","address":"0x6328bb918a01603adc91eae689b848a9ecaef26d","topics":["0x55e61a24ecdae954582245e5e611fb06905d6af967334fff4db72793bebc72a9","0x7a82a5feefcaad4a89c689412031e5f87c02b29e3fced583be5f05c7077354b7"]}]}"#)
         // expect exactly 1 POST request
-        .expect(1)
+        .expect(2)
         .with_status(200)
         .with_header("content-type", "application/json")
         .create();
@@ -2230,8 +2230,14 @@ async fn subnet_resolve() {
     client.send_particle(
         r#"
         (seq
-            (call relay ("subnet" "resolve") ["0x6dD1aFfe90415C61AeDf5c0ACcA9Cf5fD5031517"] subnet)
-            (call %init_peer_id% ("op" "return") [subnet])
+            (seq
+                (call relay ("subnet" "resolve") ["6dD1aFfe90415C61AeDf5c0ACcA9Cf5fD5031517"] subnet1)
+                (seq
+                    (call relay ("subnet" "resolve") ["0x6dD1aFfe90415C61AeDf5c0ACcA9Cf5fD5031517"] subnet2)
+                    (call relay ("subnet" "resolve") ["invalid_deal_id"] invalid)
+                )
+            )
+            (call %init_peer_id% ("op" "return") [subnet1 subnet2 invalid])
         )
     "#,
         hashmap! {
@@ -2242,6 +2248,17 @@ async fn subnet_resolve() {
     let mut result = client.receive_args().await.unwrap();
 
     let subnet: SubnetResolveResult = serde_json::from_value(result.remove(0)).unwrap();
+    let subnet_second: SubnetResolveResult = serde_json::from_value(result.remove(0)).unwrap();
+    let invalid: SubnetResolveResult = serde_json::from_value(result.remove(0)).unwrap();
+
+    assert!(!invalid.success, "invalid should be failed");
+    assert_eq!(invalid.error.len(), 1);
+    assert_eq!(
+        invalid.error[0],
+        "Invalid deal id 'invalid_deal_id': invalid length"
+    );
+
+    assert_eq!(subnet, subnet_second);
 
     assert!(subnet.success, "{:?}", subnet.error);
     assert_eq!(subnet.error.len(), 0);
diff --git a/crates/subnet-resolver/src/error.rs b/crates/subnet-resolver/src/error.rs
index bc17d065d5..f91789aa12 100644
--- a/crates/subnet-resolver/src/error.rs
+++ b/crates/subnet-resolver/src/error.rs
@@ -27,4 +27,6 @@ pub enum ResolveSubnetError {
     Empty,
     #[error("'{1}' from getPATs is not a valid PeerId")]
     InvalidPeerId(#[source] ParseError, &'static str),
+    #[error("Invalid deal id '{0}': invalid length")]
+    InvalidDealId(String),
 }
diff --git a/crates/subnet-resolver/src/resolve.rs b/crates/subnet-resolver/src/resolve.rs
index 1d2427369b..73b2034b1e 100644
--- a/crates/subnet-resolver/src/resolve.rs
+++ b/crates/subnet-resolver/src/resolve.rs
@@ -35,13 +35,13 @@ pub fn parse_chain_data(data: &str) -> Result<Vec<Token>, ChainDataError> {
     Ok(ethabi::decode(&[signature], &data)?)
 }
 
-#[derive(Serialize, Deserialize, Clone, Debug)]
+#[derive(Serialize, Deserialize, Clone, Debug, PartialEq)]
 pub struct Worker {
     pub pat_id: String,
     pub host_id: String,
     pub worker_id: Vec<String>,
 }
-#[derive(Serialize, Deserialize, Clone, Debug)]
+#[derive(Serialize, Deserialize, Clone, Debug, PartialEq)]
 pub struct SubnetResolveResult {
     pub success: bool,
     pub workers: Vec<Worker>,
@@ -92,8 +92,20 @@ fn decode_pats(data: String) -> Result<Vec<Worker>, ResolveSubnetError> {
     Ok(result)
 }
 
+pub fn validate_deal_id(deal_id: String) -> Result<String, ResolveSubnetError> {
+    // 40 hex chars + 2 for "0x" prefix
+    if deal_id.len() == 42 && deal_id.starts_with("0x") {
+        Ok(deal_id)
+    } else if deal_id.len() == 40 {
+        Ok(format!("0x{}", deal_id))
+    } else {
+        Err(ResolveSubnetError::InvalidDealId(deal_id))
+    }
+}
+
 pub fn resolve_subnet(deal_id: String, api_endpoint: &str) -> SubnetResolveResult {
     let res: Result<_, ResolveSubnetError> = try {
+        let deal_id = validate_deal_id(deal_id)?;
         // Description of the `getPATs` function from the `chain.workers` smart contract on chain
         #[allow(deprecated)]
         let input = Function {