diff --git a/packages/opencode/src/provider/provider.ts b/packages/opencode/src/provider/provider.ts
index 5ac916e412..a0ab5eb347 100644
--- a/packages/opencode/src/provider/provider.ts
+++ b/packages/opencode/src/provider/provider.ts
@@ -32,7 +32,7 @@ import { ModelStatus } from "./model-status"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 import { ProviderError } from "./error"
 
-const OPENAI_HEADER_TIMEOUT_DEFAULT = 10_000
+const OPENAI_HEADER_TIMEOUT_DEFAULT = 300_000
 
 function wrapSSE(res: Response, ms: number, ctl: AbortController) {
   if (typeof ms !== "number" || ms <= 0) return res
diff --git a/packages/opencode/test/provider/header-timeout.test.ts b/packages/opencode/test/provider/header-timeout.test.ts
index 1bd27b5cdd..fc5ab04e10 100644
--- a/packages/opencode/test/provider/header-timeout.test.ts
+++ b/packages/opencode/test/provider/header-timeout.test.ts
@@ -162,7 +162,7 @@ it.live("OpenAI API auth gets default headerTimeout", () =>
           Effect.gen(function* () {
             const provider = yield* Provider.Service
             const openai = yield* provider.getProvider(ProviderV2.ID.openai)
-            expect(openai.options.headerTimeout).toBe(10_000)
+            expect(openai.options.headerTimeout).toBe(300_000)
           }),
         )
       }),