diff --git a/Networking/Sources/Networking/HTTPRequest.swift b/Networking/Sources/Networking/HTTPRequest.swift
index 82f2ada431..a4bfa1211a 100644
--- a/Networking/Sources/Networking/HTTPRequest.swift
+++ b/Networking/Sources/Networking/HTTPRequest.swift
@@ -47,6 +47,21 @@ public struct HTTPRequest: Equatable, Sendable {
 }
 
 public extension HTTPRequest {
+    /// Initialize a `HTTPRequest` from a `URLRequest`.
+    ///
+    /// Returns `nil` if `urlRequest.url` is `nil`.
+    ///
+    /// - Parameter urlRequest: The `URLRequest` to convert.
+    ///
+    init?(from urlRequest: URLRequest) {
+        guard let url = urlRequest.url else { return nil }
+        body = urlRequest.httpBody
+        headers = urlRequest.allHTTPHeaderFields ?? [:]
+        method = HTTPMethod(rawValue: urlRequest.httpMethod ?? "GET")
+        requestID = UUID()
+        self.url = url
+    }
+
     /// Initialize a `HTTPRequest` from a `Request` instance.
     ///
     /// - Parameters:
diff --git a/Networking/Sources/Networking/HTTPService.swift b/Networking/Sources/Networking/HTTPService.swift
index af3a8bd436..e12987eedd 100644
--- a/Networking/Sources/Networking/HTTPService.swift
+++ b/Networking/Sources/Networking/HTTPService.swift
@@ -97,7 +97,8 @@ public final class HTTPService: Sendable {
     /// - Returns: The `URL` temporary location of the file.
     ///
     public func download(from urlRequest: URLRequest) async throws -> URL {
-        try await client.download(from: urlRequest)
+        let handledRequest = try await applyRequestHandlers(to: urlRequest)
+        return try await client.download(from: handledRequest)
     }
 
     /// Downloads the file at `filename` appended to the service's base URL.
@@ -110,7 +111,8 @@ public final class HTTPService: Sendable {
     ///
     public func download(filename: String) async throws -> URL {
         let url = baseURL.appendingPathComponent(filename)
-        return try await client.download(from: URLRequest(url: url))
+        let handledRequest = try await applyRequestHandlers(to: URLRequest(url: url))
+        return try await client.download(from: handledRequest)
     }
 
     /// Performs a network request.
@@ -230,6 +232,25 @@ public final class HTTPService: Sendable {
         }
     }
 
+    /// Applies any request handlers to a `URLRequest`, returning a modified copy.
+    ///
+    /// Converts the `URLRequest` to an `HTTPRequest`, runs it through the handler pipeline
+    /// (which may inject headers such as SSO cookies), then writes the resulting headers
+    /// back into the returned `URLRequest`.
+    ///
+    /// - Parameter urlRequest: The `URLRequest` to apply request handlers to.
+    /// - Returns: A copy of `urlRequest` with handler-modified headers applied.
+    ///
+    private func applyRequestHandlers(to urlRequest: URLRequest) async throws -> URLRequest {
+        guard var httpRequest = HTTPRequest(from: urlRequest) else {
+            return urlRequest
+        }
+        try await applyRequestHandlers(&httpRequest)
+        var modifiedRequest = urlRequest
+        modifiedRequest.allHTTPHeaderFields = httpRequest.headers
+        return modifiedRequest
+    }
+
     /// Applies any response handlers to the response after it's been received.
     ///
     /// - Parameters:
diff --git a/Networking/Tests/NetworkingTests/HTTPRequestTests.swift b/Networking/Tests/NetworkingTests/HTTPRequestTests.swift
index 57d3564010..344c3da7a6 100644
--- a/Networking/Tests/NetworkingTests/HTTPRequestTests.swift
+++ b/Networking/Tests/NetworkingTests/HTTPRequestTests.swift
@@ -49,6 +49,44 @@ class HTTPRequestTests: XCTestCase {
         XCTAssertEqual(subject.url, URL(string: "https://example.com/json")!)
     }
 
+    /// `init?(from:)` builds a `HTTPRequest` from a `URLRequest`.
+    func test_init_fromURLRequest() throws {
+        var urlRequest = URLRequest(url: URL(string: "https://example.com/json")!)
+        urlRequest.httpMethod = "POST"
+        urlRequest.allHTTPHeaderFields = ["Content-Type": "application/json"]
+        urlRequest.httpBody = "top secret".data(using: .utf8)
+
+        let subject = try XCTUnwrap(HTTPRequest(from: urlRequest))
+
+        XCTAssertEqual(
+            try String(data: XCTUnwrap(subject.body), encoding: .utf8),
+            "top secret",
+        )
+        XCTAssertEqual(subject.headers, ["Content-Type": "application/json"])
+        XCTAssertEqual(subject.method, .post)
+        XCTAssertEqual(subject.url, URL(string: "https://example.com/json")!)
+    }
+
+    /// `init?(from:)` uses GET and empty headers when the `URLRequest` omits them.
+    func test_init_fromURLRequest_defaultValues() throws {
+        let urlRequest = URLRequest(url: URL(string: "https://example.com")!)
+
+        let subject = try XCTUnwrap(HTTPRequest(from: urlRequest))
+
+        XCTAssertNil(subject.body)
+        XCTAssertEqual(subject.headers, [:])
+        XCTAssertEqual(subject.method, .get)
+        XCTAssertEqual(subject.url, URL(string: "https://example.com")!)
+    }
+
+    /// `init?(from:)` returns `nil` when the `URLRequest` has no URL.
+    func test_init_fromURLRequest_nilURL() {
+        var urlRequest = URLRequest(url: URL(string: "https://example.com")!)
+        urlRequest.url = nil
+
+        XCTAssertNil(HTTPRequest(from: urlRequest))
+    }
+
     /// `init(request:baseURL)` builds a `HTTPRequest` from a `Request` object.
     func test_init_request() throws {
         let subject = try HTTPRequest(
diff --git a/Networking/Tests/NetworkingTests/HTTPServiceTests.swift b/Networking/Tests/NetworkingTests/HTTPServiceTests.swift
index 4928543b57..85b555bba7 100644
--- a/Networking/Tests/NetworkingTests/HTTPServiceTests.swift
+++ b/Networking/Tests/NetworkingTests/HTTPServiceTests.swift
@@ -303,6 +303,52 @@ class HTTPServiceTests: XCTestCase {
             XCTAssertEqual(error as? TestError, .invalidResponse)
         }
     }
+}
+
+// MARK: - Download Tests
+
+extension HTTPServiceTests {
+    /// `download(from:)` applies request handlers to the URL request before downloading.
+    func test_download_fromURLRequest_appliesRequestHandlers() async throws {
+        let requestHandler = TestRequestHandler { request in
+            request.headers["Cookie"] = "sso=test-token"
+        }
+        subject = HTTPService(
+            baseURL: URL(string: "https://example.com")!,
+            client: client,
+            requestHandlers: [requestHandler],
+        )
+
+        let tempFile = FileManager.default.temporaryDirectory.appendingPathComponent("test.json")
+        try "{}".write(to: tempFile, atomically: true, encoding: .utf8)
+        client.downloadResults = [.success(tempFile)]
+
+        _ = try await subject.download(from: URLRequest(url: URL(string: "https://example.com/file.zip")!))
+
+        let downloadRequest = try XCTUnwrap(client.downloadRequests.last)
+        XCTAssertEqual(downloadRequest.allHTTPHeaderFields?["Cookie"], "sso=test-token")
+    }
+
+    /// `download(filename:)` applies request handlers to the URL request before downloading.
+    func test_download_filename_appliesRequestHandlers() async throws {
+        let requestHandler = TestRequestHandler { request in
+            request.headers["Cookie"] = "sso=test-token"
+        }
+        subject = HTTPService(
+            baseURL: URL(string: "https://example.com")!,
+            client: client,
+            requestHandlers: [requestHandler],
+        )
+
+        let tempFile = FileManager.default.temporaryDirectory.appendingPathComponent("test.json")
+        try "{}".write(to: tempFile, atomically: true, encoding: .utf8)
+        client.downloadResults = [.success(tempFile)]
+
+        _ = try await subject.download(filename: "manifest.json")
+
+        let downloadRequest = try XCTUnwrap(client.downloadRequests.last)
+        XCTAssertEqual(downloadRequest.allHTTPHeaderFields?["Cookie"], "sso=test-token")
+    }
 
     /// `download(filename:)` appends the filename to the base URL and calls the client.
     func test_download_filename() async throws {
@@ -321,37 +367,3 @@ class HTTPServiceTests: XCTestCase {
 }
 
 private struct RequestError: Error {}
-
-/// A `ResponseHandler` that captures the `retryWith` closure passed to it for inspection in tests.
-@MainActor
-private class CapturingRetryWithResponseHandler: ResponseHandler {
-    var onHandle: (((HTTPRequest) async throws -> HTTPResponse)?) -> Void
-
-    init(onHandle: @escaping (((HTTPRequest) async throws -> HTTPResponse)?) -> Void) {
-        self.onHandle = onHandle
-    }
-
-    func handle(
-        _ response: inout HTTPResponse,
-        for request: HTTPRequest,
-        retryWith: ((HTTPRequest) async throws -> HTTPResponse)?,
-    ) async throws -> HTTPResponse {
-        onHandle(retryWith)
-        return response
-    }
-}
-
-/// A `ResponseHandler` that follows a 302 redirect by calling `retryWith` with the original request.
-@MainActor
-private class RedirectFollowingResponseHandler: ResponseHandler {
-    func handle(
-        _ response: inout HTTPResponse,
-        for request: HTTPRequest,
-        retryWith: ((HTTPRequest) async throws -> HTTPResponse)?,
-    ) async throws -> HTTPResponse {
-        guard response.statusCode == 302, let retryWith else {
-            return response
-        }
-        return try await retryWith(request)
-    }
-}
diff --git a/Networking/Tests/NetworkingTests/Support/CapturingRetryWithResponseHandler.swift b/Networking/Tests/NetworkingTests/Support/CapturingRetryWithResponseHandler.swift
new file mode 100644
index 0000000000..3541dbbf92
--- /dev/null
+++ b/Networking/Tests/NetworkingTests/Support/CapturingRetryWithResponseHandler.swift
@@ -0,0 +1,20 @@
+import Networking
+
+/// A `ResponseHandler` that captures the `retryWith` closure passed to it for inspection in tests.
+@MainActor
+class CapturingRetryWithResponseHandler: ResponseHandler {
+    var onHandle: (((HTTPRequest) async throws -> HTTPResponse)?) -> Void
+
+    init(onHandle: @escaping (((HTTPRequest) async throws -> HTTPResponse)?) -> Void) {
+        self.onHandle = onHandle
+    }
+
+    func handle(
+        _ response: inout HTTPResponse,
+        for request: HTTPRequest,
+        retryWith: ((HTTPRequest) async throws -> HTTPResponse)?,
+    ) async throws -> HTTPResponse {
+        onHandle(retryWith)
+        return response
+    }
+}
diff --git a/Networking/Tests/NetworkingTests/Support/RedirectFollowingResponseHandler.swift b/Networking/Tests/NetworkingTests/Support/RedirectFollowingResponseHandler.swift
new file mode 100644
index 0000000000..00ba90fca3
--- /dev/null
+++ b/Networking/Tests/NetworkingTests/Support/RedirectFollowingResponseHandler.swift
@@ -0,0 +1,16 @@
+import Networking
+
+/// A `ResponseHandler` that follows a 302 redirect by calling `retryWith` with the original request.
+@MainActor
+class RedirectFollowingResponseHandler: ResponseHandler {
+    func handle(
+        _ response: inout HTTPResponse,
+        for request: HTTPRequest,
+        retryWith: ((HTTPRequest) async throws -> HTTPResponse)?,
+    ) async throws -> HTTPResponse {
+        guard response.statusCode == 302, let retryWith else {
+            return response
+        }
+        return try await retryWith(request)
+    }
+}