diff --git a/package.json b/package.json
index 46d23c16..16b5b885 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "root",
   "private": true,
-  "version": "4.0.3",
+  "version": "4.0.4",
   "engines": {
     "node": ">=18.0.0"
   },
diff --git a/packages/executor/src/services/EntryPointService/versions/0.0.7.ts b/packages/executor/src/services/EntryPointService/versions/0.0.7.ts
index 64592f98..517dd7dd 100644
--- a/packages/executor/src/services/EntryPointService/versions/0.0.7.ts
+++ b/packages/executor/src/services/EntryPointService/versions/0.0.7.ts
@@ -156,8 +156,8 @@ export class EntryPointV7Service implements IEntryPointService {
             gasLimit: gasLimit !== undefined ? toHex(gasLimit) : undefined,
           },
           "latest",
-          stateOverride as any,
-        ],
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
 
       const decodedResult = decodeFunctionResult({
@@ -259,8 +259,8 @@ export class EntryPointV7Service implements IEntryPointService {
             gasLimit: gasLimit !== undefined ? toHex(gasLimit) : undefined,
           },
           "latest",
-          stateOverride as any,
-        ],
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
 
       const decodedResult = decodeFunctionResult({
@@ -474,8 +474,8 @@ export class EntryPointV7Service implements IEntryPointService {
             gasLimit: gasLimit !== undefined ? toHex(gasLimit) : undefined,
           },
           "latest",
-          stateOverride,
-        ],
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
 
       const res = decodeFunctionResult({
@@ -503,7 +503,11 @@ export class EntryPointV7Service implements IEntryPointService {
     try {
       const errorResult = await this.publicClient.request({
         method: "eth_call",
-        params: [{ to: this.address, data }, "latest", stateOverride],
+        params: [
+          { to: this.address, data },
+          "latest",
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
       return this.parseValidationResult(userOp, errorResult);
     } catch (error: any) {
diff --git a/packages/executor/src/services/EntryPointService/versions/0.0.8.ts b/packages/executor/src/services/EntryPointService/versions/0.0.8.ts
index 3dc8fa48..4d83f186 100644
--- a/packages/executor/src/services/EntryPointService/versions/0.0.8.ts
+++ b/packages/executor/src/services/EntryPointService/versions/0.0.8.ts
@@ -181,8 +181,8 @@ export class EntryPointV8Service implements IEntryPointService {
             gasLimit: gasLimit !== undefined ? toHex(gasLimit) : undefined,
           },
           "latest",
-          stateOverride as any,
-        ],
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
 
       const decodedResult = decodeFunctionResult({
@@ -284,8 +284,8 @@ export class EntryPointV8Service implements IEntryPointService {
             gasLimit: gasLimit !== undefined ? toHex(gasLimit) : undefined,
           },
           "latest",
-          stateOverride as any,
-        ],
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
 
       const decodedResult = decodeFunctionResult({
@@ -509,8 +509,8 @@ export class EntryPointV8Service implements IEntryPointService {
             gasLimit: gasLimit !== undefined ? toHex(gasLimit) : undefined,
           },
           "latest",
-          stateOverride,
-        ],
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
 
       const res = decodeFunctionResult({
@@ -539,7 +539,11 @@ export class EntryPointV8Service implements IEntryPointService {
     try {
       const errorResult = await this.publicClient.request({
         method: "eth_call",
-        params: [{ to: this.address, data }, "latest", stateOverride],
+        params: [
+          { to: this.address, data },
+          "latest",
+          ...(stateOverride ? [stateOverride] : []),
+        ] as any,
       });
       return this.parseValidationResult(userOp, errorResult);
     } catch (error: any) {
diff --git a/packages/executor/test/unit/services/eth_call_state_override_params.test.ts b/packages/executor/test/unit/services/eth_call_state_override_params.test.ts
new file mode 100644
index 00000000..99d6ef8c
--- /dev/null
+++ b/packages/executor/test/unit/services/eth_call_state_override_params.test.ts
@@ -0,0 +1,105 @@
+import { describe, it, expect } from "vitest";
+import { UserOperation } from "@skandha/types/lib/contracts/UserOperation";
+import { EntryPointV7Service } from "../../../src/services/EntryPointService/versions/0.0.7";
+import { EntryPointV8Service } from "../../../src/services/EntryPointService/versions/0.0.8";
+
+const ENTRY_POINT = "0x0000000071727De22E5E9d8BAf0edAc6f37da032";
+const PIMLICO_SIMULATIONS = "0x000000000049883a1a4f4b3c1b1b0ed0c43e5e1e";
+const EP_SIMULATIONS = "0x00000000009a9d4ba6ac9a1c0c67f2dd6a2c1a3f";
+
+const userOp: UserOperation = {
+  sender: "0x54E3d8E0F9800440581D6d82C7A85F1167090d98",
+  nonce: "0x01",
+  callData: "0x",
+  callGasLimit: "0x3e93f",
+  verificationGasLimit: "0x1aaf8",
+  preVerificationGas: "0x10a2b",
+  maxFeePerGas: "0xd59f80",
+  maxPriorityFeePerGas: "0x1e8480",
+  signature: "0x",
+};
+
+const networkConfig = {
+  pimlicoSimulationsContract: PIMLICO_SIMULATIONS,
+  epSimulationsContract: EP_SIMULATIONS,
+  binarySearchMaxRetries: 3,
+  gasFeeInSimulation: false,
+} as any;
+
+const logger = {
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  debug: () => {},
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  info: () => {},
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  warn: () => {},
+  // eslint-disable-next-line @typescript-eslint/no-empty-function
+  error: () => {},
+} as any;
+
+/**
+ * Records every eth_call params array, then fails the call so we never have to
+ * mock a decodable return value - the shape of `params` is the whole point.
+ */
+function recordingClient(): { client: any; params: unknown[][] } {
+  const params: unknown[][] = [];
+  const client = {
+    request: async (req: any) => {
+      if (req.method === "eth_call") params.push(req.params);
+      throw new Error("recorded");
+    },
+  };
+  return { client, params };
+}
+
+type Service = EntryPointV7Service | EntryPointV8Service;
+
+const versions: [string, (client: any) => Service][] = [
+  [
+    "EntryPoint v0.0.7",
+    (client) =>
+      new EntryPointV7Service(ENTRY_POINT, networkConfig, client, logger),
+  ],
+  [
+    "EntryPoint v0.0.8",
+    (client) =>
+      new EntryPointV8Service(ENTRY_POINT, networkConfig, client, logger),
+  ],
+];
+
+describe.each(versions)(
+  "%s eth_call state override param",
+  (_name, makeService) => {
+    it("omits the third param entirely when no state override is supplied", async () => {
+      const { client, params } = recordingClient();
+      await makeService(client)
+        .simulateHandleOpUsingSimulatorContracts(userOp)
+        .catch(() => undefined);
+
+      expect(params.length).toBeGreaterThan(0);
+      for (const p of params) {
+        // A trailing `undefined` JSON-serializes to `null`, which strict nodes
+        // (e.g. Monad) reject with -32602 Invalid params before any execution.
+        expect(p).toHaveLength(2);
+        expect(p[1]).toEqual("latest");
+        expect(JSON.stringify(p)).not.toContain("null");
+      }
+    });
+
+    it("passes the override as the third param when one is supplied", async () => {
+      const { client, params } = recordingClient();
+      const overrides = {
+        "0x00000000000000000000000000000000deadbeef": { balance: "0x1" },
+      } as any;
+      await makeService(client)
+        .simulateHandleOpUsingSimulatorContracts(userOp, overrides)
+        .catch(() => undefined);
+
+      expect(params.length).toBeGreaterThan(0);
+      for (const p of params) {
+        expect(p).toHaveLength(3);
+        expect(p[2]).toEqual(overrides);
+      }
+    });
+  }
+);