diff --git a/src/api/providers/__tests__/openrouter.spec.ts b/src/api/providers/__tests__/openrouter.spec.ts
index ae36fc1399..7a0f664b25 100644
--- a/src/api/providers/__tests__/openrouter.spec.ts
+++ b/src/api/providers/__tests__/openrouter.spec.ts
@@ -321,3 +321,71 @@ describe("OpenRouterHandler", () => {
 		})
 	})
 })
+
+describe("reasoning effort mapping (OpenRouter)", () => {
+	it("passes 'minimal' through in reasoning.effort for OpenRouter requests", async () => {
+		const handler = new OpenRouterHandler({
+			openRouterApiKey: "test-key",
+			openRouterModelId: "openai/o1-pro",
+			reasoningEffort: "minimal",
+		} as ApiHandlerOptions)
+
+		// Prepare a model that supports reasoning effort (not budget)
+		;(handler as any).models = {
+			"openai/o1-pro": {
+				maxTokens: 8192,
+				contextWindow: 200000,
+				supportsImages: true,
+				supportsPromptCache: true,
+				inputPrice: 0.0,
+				outputPrice: 0.0,
+				description: "o1-pro test",
+				supportsReasoningEffort: true,
+			},
+		}
+
+		// Ensure endpoints map is empty so base model info is used
+		;(handler as any).endpoints = {}
+
+		// Mock OpenAI client call
+		const mockCreate = vitest.fn().mockResolvedValue({
+			async *[Symbol.asyncIterator]() {
+				yield {
+					id: "openai/o1-pro",
+					choices: [{ delta: { content: "ok" } }],
+				}
+				yield {
+					id: "usage-id",
+					choices: [{ delta: {} }],
+					usage: { prompt_tokens: 1, completion_tokens: 1, cost: 0 },
+				}
+			},
+		})
+		;(OpenAI as any).prototype.chat = {
+			completions: { create: mockCreate },
+		} as any
+
+		const systemPrompt = "system"
+		const messages: Anthropic.Messages.MessageParam[] = [{ role: "user", content: "hello" }]
+
+		// Stub fetchModel to use the handler's getModel (which applies getModelParams -> getOpenRouterReasoning)
+		const realGetModel = (handler as any).getModel.bind(handler)
+		;(handler as any).fetchModel = vitest.fn().mockImplementation(async () => realGetModel())
+
+		// Trigger a request
+		const gen = handler.createMessage(systemPrompt, messages)
+		// Drain iterator to ensure call is made
+		for await (const _ of gen) {
+			// noop
+		}
+
+		// Verify the API call included the normalized effort
+		expect(mockCreate).toHaveBeenCalledWith(
+			expect.objectContaining({
+				model: "openai/o1-pro",
+				reasoning: { effort: "minimal" }, // 'minimal' should be preserved for OpenRouter
+				stream: true,
+			}),
+		)
+	})
+})
diff --git a/src/api/transform/reasoning.ts b/src/api/transform/reasoning.ts
index 100b1c2684..fff288e3f0 100644
--- a/src/api/transform/reasoning.ts
+++ b/src/api/transform/reasoning.ts
@@ -30,14 +30,21 @@ export const getOpenRouterReasoning = ({
 	reasoningBudget,
 	reasoningEffort,
 	settings,
-}: GetModelReasoningOptions): OpenRouterReasoningParams | undefined =>
-	shouldUseReasoningBudget({ model, settings })
-		? { max_tokens: reasoningBudget }
-		: shouldUseReasoningEffort({ model, settings })
-			? reasoningEffort
-				? { effort: reasoningEffort }
-				: undefined
-			: undefined
+}: GetModelReasoningOptions): OpenRouterReasoningParams | undefined => {
+	// If the model uses a budget-style reasoning config on OpenRouter, pass it through.
+	if (shouldUseReasoningBudget({ model, settings })) {
+		return { max_tokens: reasoningBudget! }
+	}
+
+	// Otherwise, if we support traditional reasoning effort, pass through the effort.
+	// Note: Some models (e.g., GPT‑5 via OpenRouter) may support "minimal".
+	if (shouldUseReasoningEffort({ model, settings })) {
+		if (!reasoningEffort) return undefined
+		return { effort: reasoningEffort }
+	}
+
+	return undefined
+}
 
 export const getAnthropicReasoning = ({
 	model,