diff --git a/Sources/GoogleAI/GenerativeAIRequest.swift b/Sources/GoogleAI/GenerativeAIRequest.swift
index 1afd65d..d468576 100644
--- a/Sources/GoogleAI/GenerativeAIRequest.swift
+++ b/Sources/GoogleAI/GenerativeAIRequest.swift
@@ -26,9 +26,8 @@ protocol GenerativeAIRequest: Encodable {
 /// Configuration parameters for sending requests to the backend.
 @available(iOS 15.0, macOS 11.0, macCatalyst 15.0, *)
 public struct RequestOptions {
-  /// The request’s timeout interval in seconds; if not specified uses the default value for a
-  /// `URLRequest`.
-  let timeout: TimeInterval?
+  /// The request’s timeout interval in seconds.
+  let timeout: TimeInterval
 
   /// The API version to use in requests to the backend.
   let apiVersion: String
@@ -36,10 +35,9 @@ public struct RequestOptions {
   /// Initializes a request options object.
   ///
   /// - Parameters:
-  ///   - timeout The request’s timeout interval in seconds; if not specified uses the default value
-  ///   for a `URLRequest`.
-  ///   - apiVersion The API version to use in requests to the backend; defaults to "v1beta".
-  public init(timeout: TimeInterval? = nil, apiVersion: String = "v1beta") {
+  ///   - timeout: The request’s timeout interval in seconds; defaults to 300 seconds (5 minutes).
+  ///   - apiVersion: The API version to use in requests to the backend; defaults to "v1beta".
+  public init(timeout: TimeInterval = 300.0, apiVersion: String = "v1beta") {
     self.timeout = timeout
     self.apiVersion = apiVersion
   }
diff --git a/Sources/GoogleAI/GenerativeAIService.swift b/Sources/GoogleAI/GenerativeAIService.swift
index 8d90473..0f32d6a 100644
--- a/Sources/GoogleAI/GenerativeAIService.swift
+++ b/Sources/GoogleAI/GenerativeAIService.swift
@@ -156,10 +156,7 @@ struct GenerativeAIService {
     let encoder = JSONEncoder()
     encoder.keyEncodingStrategy = .convertToSnakeCase
     urlRequest.httpBody = try encoder.encode(request)
-
-    if let timeoutInterval = request.options.timeout {
-      urlRequest.timeoutInterval = timeoutInterval
-    }
+    urlRequest.timeoutInterval = request.options.timeout
 
     return urlRequest
   }
diff --git a/Tests/GoogleAITests/GenerativeModelTests.swift b/Tests/GoogleAITests/GenerativeModelTests.swift
index ccd8979..5a20343 100644
--- a/Tests/GoogleAITests/GenerativeModelTests.swift
+++ b/Tests/GoogleAITests/GenerativeModelTests.swift
@@ -611,6 +611,20 @@ final class GenerativeModelTests: XCTestCase {
     XCTAssertEqual(response.candidates.count, 1)
   }
 
+  func testGenerateContent_requestOptions_defaultTimeout() async throws {
+    let expectedTimeout = 300.0 // Default in timeout in RequestOptions()
+    MockURLProtocol
+      .requestHandler = try httpRequestHandler(
+        forResource: "unary-success-basic-reply-short",
+        withExtension: "json",
+        timeout: expectedTimeout
+      )
+
+    let response = try await model.generateContent(testPrompt)
+
+    XCTAssertEqual(response.candidates.count, 1)
+  }
+
   // MARK: - Generate Content (Streaming)
 
   func testGenerateContentStream_failureInvalidAPIKey() async throws {
@@ -967,6 +981,25 @@ final class GenerativeModelTests: XCTestCase {
     XCTAssertEqual(responses, 1)
   }
 
+  func testGenerateContentStream_requestOptions_defaultTimeout() async throws {
+    let expectedTimeout = 300.0 // Default in timeout in RequestOptions()
+    MockURLProtocol
+      .requestHandler = try httpRequestHandler(
+        forResource: "streaming-success-basic-reply-short",
+        withExtension: "txt",
+        timeout: expectedTimeout
+      )
+
+    var responses = 0
+    let stream = model.generateContentStream(testPrompt)
+    for try await content in stream {
+      XCTAssertNotNil(content.text)
+      responses += 1
+    }
+
+    XCTAssertEqual(responses, 1)
+  }
+
   // MARK: - Count Tokens
 
   func testCountTokens_succeeds() async throws {
@@ -1019,6 +1052,20 @@ final class GenerativeModelTests: XCTestCase {
     XCTAssertEqual(response.totalTokens, 6)
   }
 
+  func testCountTokens_requestOptions_defaultTimeout() async throws {
+    let expectedTimeout = 300.0
+    MockURLProtocol
+      .requestHandler = try httpRequestHandler(
+        forResource: "success-total-tokens",
+        withExtension: "json",
+        timeout: expectedTimeout
+      )
+
+    let response = try await model.countTokens(testPrompt)
+
+    XCTAssertEqual(response.totalTokens, 6)
+  }
+
   // MARK: - Model Resource Name
 
   func testModelResourceName_noPrefix() async throws {
@@ -1067,8 +1114,8 @@ final class GenerativeModelTests: XCTestCase {
   private func httpRequestHandler(forResource name: String,
                                   withExtension ext: String,
                                   statusCode: Int = 200,
-                                  timeout: TimeInterval = URLRequest
-                                    .defaultTimeoutInterval()) throws -> ((URLRequest) throws -> (
+                                  timeout: TimeInterval = RequestOptions()
+                                    .timeout) throws -> ((URLRequest) throws -> (
     URLResponse,
     AsyncLineSequence<URL.AsyncBytes>?
   )) {