diff --git a/packages/types/src/providers/gemini.ts b/packages/types/src/providers/gemini.ts
index a7225c7330..70fcc2cee3 100644
--- a/packages/types/src/providers/gemini.ts
+++ b/packages/types/src/providers/gemini.ts
@@ -6,25 +6,6 @@ export type GeminiModelId = keyof typeof geminiModels
 export const geminiDefaultModelId: GeminiModelId = "gemini-2.0-flash-001"
 
 export const geminiModels = {
-	"gemini-2.5-flash-preview-04-17:thinking": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0.15,
-		outputPrice: 3.5,
-		maxThinkingTokens: 24_576,
-		supportsReasoningBudget: true,
-		requiredReasoningBudget: true,
-	},
-	"gemini-2.5-flash-preview-04-17": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0.15,
-		outputPrice: 0.6,
-	},
 	"gemini-2.5-flash-preview-05-20:thinking": {
 		maxTokens: 65_535,
 		contextWindow: 1_048_576,
@@ -60,16 +41,8 @@ export const geminiModels = {
 		maxThinkingTokens: 24_576,
 		supportsReasoningBudget: true,
 	},
-	"gemini-2.5-pro-exp-03-25": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
-	"gemini-2.5-pro-preview-03-25": {
-		maxTokens: 65_535,
+	"gemini-2.5-pro": {
+		maxTokens: 64_000,
 		contextWindow: 1_048_576,
 		supportsImages: true,
 		supportsPromptCache: true,
@@ -77,6 +50,9 @@ export const geminiModels = {
 		outputPrice: 15,
 		cacheReadsPrice: 0.625,
 		cacheWritesPrice: 4.5,
+		maxThinkingTokens: 32_768,
+		supportsReasoningBudget: true,
+		requiredReasoningBudget: true,
 		tiers: [
 			{
 				contextWindow: 200_000,
@@ -92,7 +68,48 @@ export const geminiModels = {
 			},
 		],
 	},
-	"gemini-2.5-pro-preview-05-06": {
+	"gemini-2.0-flash-001": {
+		maxTokens: 8192,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: true,
+		inputPrice: 0.1,
+		outputPrice: 0.4,
+		cacheReadsPrice: 0.025,
+		cacheWritesPrice: 1.0,
+	},
+	"gemini-2.0-flash-lite-preview-02-05": {
+		maxTokens: 8192,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.5-flash-lite-preview-06-17": {
+		maxTokens: 64_000,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: true,
+		inputPrice: 0.1,
+		outputPrice: 0.4,
+		cacheReadsPrice: 0.025,
+		cacheWritesPrice: 1.0,
+		supportsReasoningBudget: true,
+		maxThinkingTokens: 24_576,
+	},
+} as const satisfies Record<string, ModelInfo>
+
+export const legacyGeminiModels = {
+	"gemini-2.5-pro-exp-03-25": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.5-pro-preview-03-25": {
 		maxTokens: 65_535,
 		contextWindow: 1_048_576,
 		supportsImages: true,
@@ -116,7 +133,7 @@ export const geminiModels = {
 			},
 		],
 	},
-	"gemini-2.5-pro-preview-06-05": {
+	"gemini-2.5-pro-preview-05-06": {
 		maxTokens: 65_535,
 		contextWindow: 1_048_576,
 		supportsImages: true,
@@ -125,8 +142,6 @@ export const geminiModels = {
 		outputPrice: 15,
 		cacheReadsPrice: 0.625,
 		cacheWritesPrice: 4.5,
-		maxThinkingTokens: 32_768,
-		supportsReasoningBudget: true,
 		tiers: [
 			{
 				contextWindow: 200_000,
@@ -142,8 +157,8 @@ export const geminiModels = {
 			},
 		],
 	},
-	"gemini-2.5-pro": {
-		maxTokens: 64_000,
+	"gemini-2.5-pro-preview-06-05": {
+		maxTokens: 65_535,
 		contextWindow: 1_048_576,
 		supportsImages: true,
 		supportsPromptCache: true,
@@ -153,7 +168,6 @@ export const geminiModels = {
 		cacheWritesPrice: 4.5,
 		maxThinkingTokens: 32_768,
 		supportsReasoningBudget: true,
-		requiredReasoningBudget: true,
 		tiers: [
 			{
 				contextWindow: 200_000,
@@ -169,56 +183,6 @@ export const geminiModels = {
 			},
 		],
 	},
-	"gemini-2.0-flash-001": {
-		maxTokens: 8192,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: true,
-		inputPrice: 0.1,
-		outputPrice: 0.4,
-		cacheReadsPrice: 0.025,
-		cacheWritesPrice: 1.0,
-	},
-	"gemini-2.0-flash-lite-preview-02-05": {
-		maxTokens: 8192,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
-	"gemini-2.0-pro-exp-02-05": {
-		maxTokens: 8192,
-		contextWindow: 2_097_152,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
-	"gemini-2.0-flash-thinking-exp-01-21": {
-		maxTokens: 65_536,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
-	"gemini-2.0-flash-thinking-exp-1219": {
-		maxTokens: 8192,
-		contextWindow: 32_767,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
-	"gemini-2.0-flash-exp": {
-		maxTokens: 8192,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
 	"gemini-1.5-flash-002": {
 		maxTokens: 8192,
 		contextWindow: 1_048_576,
@@ -283,16 +247,105 @@ export const geminiModels = {
 		inputPrice: 0,
 		outputPrice: 0,
 	},
-	"gemini-2.5-flash-lite-preview-06-17": {
-		maxTokens: 64_000,
+	"gemini-2.0-pro-exp-02-05": {
+		maxTokens: 8192,
+		contextWindow: 2_097_152,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.0-flash-thinking-exp-1219": {
+		maxTokens: 8192,
+		contextWindow: 32_767,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.0-flash-thinking-exp-01-21": {
+		maxTokens: 65_536,
 		contextWindow: 1_048_576,
 		supportsImages: true,
-		supportsPromptCache: true,
-		inputPrice: 0.1,
-		outputPrice: 0.4,
-		cacheReadsPrice: 0.025,
-		cacheWritesPrice: 1.0,
-		supportsReasoningBudget: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.5-flash-preview-04-17:thinking": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0.15,
+		outputPrice: 3.5,
 		maxThinkingTokens: 24_576,
+		supportsReasoningBudget: true,
+		requiredReasoningBudget: true,
+	},
+	"gemini-2.5-flash-preview-04-17": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0.15,
+		outputPrice: 0.6,
+	},
+	"gemini-2.0-flash-exp": {
+		maxTokens: 8192,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
 	},
 } as const satisfies Record<string, ModelInfo>
+
+/**
+ * Maps legacy Gemini model IDs to current supported models
+ */
+export function mapLegacyGeminiModel(modelId: string): GeminiModelId {
+	if (modelId in geminiModels) {
+		return modelId as GeminiModelId
+	}
+
+	if (modelId in legacyGeminiModels) {
+		if (modelId.startsWith("gemini-2.5-pro-preview-")) {
+			return "gemini-2.5-pro"
+		}
+
+		if (modelId.startsWith("gemini-1.5-pro-")) {
+			return geminiDefaultModelId
+		}
+
+		if (modelId.startsWith("gemini-1.5-flash-")) {
+			return geminiDefaultModelId
+		}
+
+		if (modelId.startsWith("gemini-2.5-pro-exp-")) {
+			return "gemini-2.5-pro"
+		}
+
+		if (modelId === "gemini-exp-1206") {
+			return geminiDefaultModelId
+		}
+
+		if (modelId === "gemini-2.0-pro-exp-02-05") {
+			return "gemini-2.5-pro"
+		}
+
+		if (
+			modelId === "gemini-2.0-flash-thinking-exp-1219" ||
+			modelId === "gemini-2.0-flash-thinking-exp-01-21" ||
+			modelId === "gemini-2.5-flash-preview-04-17" ||
+			modelId === "gemini-2.5-flash-preview-04-17:thinking"
+		) {
+			return "gemini-2.5-flash-preview-05-20"
+		}
+
+		if (modelId === "gemini-2.0-flash-exp") {
+			return geminiDefaultModelId
+		}
+	}
+
+	return geminiDefaultModelId
+}
diff --git a/packages/types/src/providers/vertex.ts b/packages/types/src/providers/vertex.ts
index ee8a56ae2c..cf2af9f8ee 100644
--- a/packages/types/src/providers/vertex.ts
+++ b/packages/types/src/providers/vertex.ts
@@ -37,51 +37,6 @@ export const vertexModels = {
 		maxThinkingTokens: 24_576,
 		supportsReasoningBudget: true,
 	},
-	"gemini-2.5-flash-preview-04-17:thinking": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0.15,
-		outputPrice: 3.5,
-		maxThinkingTokens: 24_576,
-		supportsReasoningBudget: true,
-		requiredReasoningBudget: true,
-	},
-	"gemini-2.5-flash-preview-04-17": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0.15,
-		outputPrice: 0.6,
-	},
-	"gemini-2.5-pro-preview-03-25": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: true,
-		inputPrice: 2.5,
-		outputPrice: 15,
-	},
-	"gemini-2.5-pro-preview-05-06": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: true,
-		inputPrice: 2.5,
-		outputPrice: 15,
-	},
-	"gemini-2.5-pro-preview-06-05": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: true,
-		inputPrice: 2.5,
-		outputPrice: 15,
-		maxThinkingTokens: 32_768,
-		supportsReasoningBudget: true,
-	},
 	"gemini-2.5-pro": {
 		maxTokens: 64_000,
 		contextWindow: 1_048_576,
@@ -107,22 +62,6 @@ export const vertexModels = {
 			},
 		],
 	},
-	"gemini-2.5-pro-exp-03-25": {
-		maxTokens: 65_535,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
-	"gemini-2.0-pro-exp-02-05": {
-		maxTokens: 8192,
-		contextWindow: 2_097_152,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
 	"gemini-2.0-flash-001": {
 		maxTokens: 8192,
 		contextWindow: 1_048_576,
@@ -139,30 +78,6 @@ export const vertexModels = {
 		inputPrice: 0.075,
 		outputPrice: 0.3,
 	},
-	"gemini-2.0-flash-thinking-exp-01-21": {
-		maxTokens: 8192,
-		contextWindow: 32_768,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 0,
-		outputPrice: 0,
-	},
-	"gemini-1.5-flash-002": {
-		maxTokens: 8192,
-		contextWindow: 1_048_576,
-		supportsImages: true,
-		supportsPromptCache: true,
-		inputPrice: 0.075,
-		outputPrice: 0.3,
-	},
-	"gemini-1.5-pro-002": {
-		maxTokens: 8192,
-		contextWindow: 2_097_152,
-		supportsImages: true,
-		supportsPromptCache: false,
-		inputPrice: 1.25,
-		outputPrice: 5,
-	},
 	"claude-sonnet-4@20250514": {
 		maxTokens: 8192,
 		contextWindow: 200_000,
@@ -330,3 +245,133 @@ export const VERTEX_REGIONS = [
 	{ value: "me-central1", label: "me-central1" },
 	{ value: "africa-south1", label: "africa-south1" },
 ]
+
+export const legacyVertexModels = {
+	"gemini-1.5-flash-002": {
+		maxTokens: 8192,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: true,
+		inputPrice: 0.075,
+		outputPrice: 0.3,
+	},
+	"gemini-1.5-pro-002": {
+		maxTokens: 8192,
+		contextWindow: 2_097_152,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 1.25,
+		outputPrice: 5,
+	},
+	"gemini-2.5-pro-exp-03-25": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.5-pro-preview-03-25": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: true,
+		inputPrice: 2.5,
+		outputPrice: 15,
+	},
+	"gemini-2.5-pro-preview-05-06": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: true,
+		inputPrice: 2.5,
+		outputPrice: 15,
+	},
+	"gemini-2.5-pro-preview-06-05": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: true,
+		inputPrice: 2.5,
+		outputPrice: 15,
+		maxThinkingTokens: 32_768,
+		supportsReasoningBudget: true,
+	},
+	"gemini-2.0-pro-exp-02-05": {
+		maxTokens: 8192,
+		contextWindow: 2_097_152,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.0-flash-thinking-exp-01-21": {
+		maxTokens: 8192,
+		contextWindow: 32_768,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0,
+		outputPrice: 0,
+	},
+	"gemini-2.5-flash-preview-04-17:thinking": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0.15,
+		outputPrice: 3.5,
+		maxThinkingTokens: 24_576,
+		supportsReasoningBudget: true,
+		requiredReasoningBudget: true,
+	},
+	"gemini-2.5-flash-preview-04-17": {
+		maxTokens: 65_535,
+		contextWindow: 1_048_576,
+		supportsImages: true,
+		supportsPromptCache: false,
+		inputPrice: 0.15,
+		outputPrice: 0.6,
+	},
+} as const satisfies Record<string, ModelInfo>
+
+/**
+ * Maps legacy Vertex model IDs to current supported models
+ */
+export function mapLegacyVertexModel(modelId: string): VertexModelId {
+	if (modelId in vertexModels) {
+		return modelId as VertexModelId
+	}
+
+	if (modelId in legacyVertexModels) {
+		if (modelId.startsWith("gemini-2.5-pro-preview-")) {
+			return "gemini-2.5-pro"
+		}
+
+		if (modelId.startsWith("gemini-1.5-pro-")) {
+			return "gemini-2.0-flash-001"
+		}
+
+		if (modelId.startsWith("gemini-1.5-flash-")) {
+			return "gemini-2.0-flash-001"
+		}
+
+		if (modelId.startsWith("gemini-2.5-pro-exp-")) {
+			return "gemini-2.5-pro"
+		}
+
+		if (modelId === "gemini-2.0-pro-exp-02-05") {
+			return "gemini-2.5-pro"
+		}
+
+		if (
+			modelId === "gemini-2.0-flash-thinking-exp-1219" ||
+			modelId === "gemini-2.0-flash-thinking-exp-01-21" ||
+			modelId === "gemini-2.5-flash-preview-04-17" ||
+			modelId === "gemini-2.5-flash-preview-04-17:thinking"
+		) {
+			return "gemini-2.5-flash-preview-05-20"
+		}
+	}
+
+	return vertexDefaultModelId
+}
diff --git a/src/api/providers/__tests__/gemini.spec.ts b/src/api/providers/__tests__/gemini.spec.ts
index 812c1ae1a6..743581276f 100644
--- a/src/api/providers/__tests__/gemini.spec.ts
+++ b/src/api/providers/__tests__/gemini.spec.ts
@@ -7,7 +7,7 @@ import { type ModelInfo, geminiDefaultModelId } from "@roo-code/types"
 import { t } from "i18next"
 import { GeminiHandler } from "../gemini"
 
-const GEMINI_20_FLASH_THINKING_NAME = "gemini-2.0-flash-thinking-exp-1219"
+const GEMINI_25_FLASH_PREVIEW_05_20_NAME = "gemini-2.5-flash-preview-05-20"
 
 describe("GeminiHandler", () => {
 	let handler: GeminiHandler
@@ -20,7 +20,7 @@ describe("GeminiHandler", () => {
 
 		handler = new GeminiHandler({
 			apiKey: "test-key",
-			apiModelId: GEMINI_20_FLASH_THINKING_NAME,
+			apiModelId: GEMINI_25_FLASH_PREVIEW_05_20_NAME,
 			geminiApiKey: "test-key",
 		})
 
@@ -37,7 +37,7 @@ describe("GeminiHandler", () => {
 	describe("constructor", () => {
 		it("should initialize with provided config", () => {
 			expect(handler["options"].geminiApiKey).toBe("test-key")
-			expect(handler["options"].apiModelId).toBe(GEMINI_20_FLASH_THINKING_NAME)
+			expect(handler["options"].apiModelId).toBe(GEMINI_25_FLASH_PREVIEW_05_20_NAME)
 		})
 	})
 
@@ -76,12 +76,19 @@ describe("GeminiHandler", () => {
 			expect(chunks.length).toBe(3)
 			expect(chunks[0]).toEqual({ type: "text", text: "Hello" })
 			expect(chunks[1]).toEqual({ type: "text", text: " world!" })
-			expect(chunks[2]).toEqual({ type: "usage", inputTokens: 10, outputTokens: 5 })
+			expect(chunks[2]).toEqual({
+				type: "usage",
+				inputTokens: 10,
+				outputTokens: 5,
+				cacheReadTokens: undefined,
+				reasoningTokens: undefined,
+				totalCost: expect.any(Number),
+			})
 
 			// Verify the call to generateContentStream
 			expect(handler["client"].models.generateContentStream).toHaveBeenCalledWith(
 				expect.objectContaining({
-					model: GEMINI_20_FLASH_THINKING_NAME,
+					model: GEMINI_25_FLASH_PREVIEW_05_20_NAME,
 					config: expect.objectContaining({
 						temperature: 0,
 						systemInstruction: systemPrompt,
@@ -116,7 +123,7 @@ describe("GeminiHandler", () => {
 
 			// Verify the call to generateContent
 			expect(handler["client"].models.generateContent).toHaveBeenCalledWith({
-				model: GEMINI_20_FLASH_THINKING_NAME,
+				model: GEMINI_25_FLASH_PREVIEW_05_20_NAME,
 				contents: [{ role: "user", parts: [{ text: "Test prompt" }] }],
 				config: {
 					httpOptions: undefined,
@@ -148,10 +155,10 @@ describe("GeminiHandler", () => {
 	describe("getModel", () => {
 		it("should return correct model info", () => {
 			const modelInfo = handler.getModel()
-			expect(modelInfo.id).toBe(GEMINI_20_FLASH_THINKING_NAME)
+			expect(modelInfo.id).toBe(GEMINI_25_FLASH_PREVIEW_05_20_NAME)
 			expect(modelInfo.info).toBeDefined()
-			expect(modelInfo.info.maxTokens).toBe(8192)
-			expect(modelInfo.info.contextWindow).toBe(32_767)
+			expect(modelInfo.info.maxTokens).toBe(65_535)
+			expect(modelInfo.info.contextWindow).toBe(1_048_576)
 		})
 
 		it("should return default model if invalid model specified", () => {
@@ -164,6 +171,116 @@ describe("GeminiHandler", () => {
 		})
 	})
 
+	describe("legacy model migration", () => {
+		it("should map gemini-2.5-pro-preview-{dates} to gemini-2.5-pro", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.5-pro-preview-03-25",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+
+		it("should map gemini-1.5-pro-{variants} to gemini-2.0-flash-001", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-1.5-pro-002",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.0-flash-001")
+		})
+
+		it("should map gemini-1.5-flash-{variants} to gemini-2.0-flash-001", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-1.5-flash-002",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.0-flash-001")
+		})
+
+		it("should map experimental gemini-2.5-pro-exp-03-25 to gemini-2.5-pro", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.5-pro-exp-03-25",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+
+		it("should map gemini-exp-1206 to gemini-2.0-flash-001", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-exp-1206",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.0-flash-001")
+		})
+
+		it("should map gemini-2.0-pro-exp-02-05 to gemini-2.5-pro", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.0-pro-exp-02-05",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+
+		it("should map gemini-2.0-flash-thinking-exp-1219 to gemini-2.5-flash-preview-05-20", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.0-flash-thinking-exp-1219",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-flash-preview-05-20")
+		})
+
+		it("should map gemini-2.0-flash-thinking-exp-01-21 to gemini-2.5-flash-preview-05-20", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.0-flash-thinking-exp-01-21",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-flash-preview-05-20")
+		})
+
+		it("should map gemini-2.5-flash-preview-04-17 to gemini-2.5-flash-preview-05-20", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.5-flash-preview-04-17",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-flash-preview-05-20")
+		})
+
+		it("should map gemini-2.0-flash-exp to gemini-2.0-flash-001", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.0-flash-exp",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.0-flash-001")
+		})
+
+		it("should map gemini-2.5-flash-preview-04-17:thinking to gemini-2.5-flash-preview-05-20", () => {
+			const legacyHandler = new GeminiHandler({
+				apiModelId: "gemini-2.5-flash-preview-04-17:thinking",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-flash-preview-05-20")
+		})
+
+		it("should keep current models as-is", () => {
+			const currentHandler = new GeminiHandler({
+				apiModelId: "gemini-2.5-pro",
+				geminiApiKey: "test-key",
+			})
+			const modelInfo = currentHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+	})
+
 	describe("calculateCost", () => {
 		// Mock ModelInfo based on gemini-1.5-flash-latest pricing (per 1M tokens)
 		// Removed 'id' and 'name' as they are not part of ModelInfo type directly
diff --git a/src/api/providers/__tests__/vertex.spec.ts b/src/api/providers/__tests__/vertex.spec.ts
index d147e79ba8..5aa76ff0f7 100644
--- a/src/api/providers/__tests__/vertex.spec.ts
+++ b/src/api/providers/__tests__/vertex.spec.ts
@@ -138,4 +138,106 @@ describe("VertexHandler", () => {
 			expect(modelInfo.info.contextWindow).toBe(1048576)
 		})
 	})
+
+	describe("legacy model migration", () => {
+		it("should map gemini-2.5-pro-preview-{dates} to gemini-2.5-pro", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-2.5-pro-preview-03-25",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+
+		it("should map gemini-1.5-pro-{variants} to gemini-2.0-flash-001", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-1.5-pro-002",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.0-flash-001")
+		})
+
+		it("should map gemini-1.5-flash-{variants} to gemini-2.0-flash-001", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-1.5-flash-002",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.0-flash-001")
+		})
+
+		it("should map experimental gemini-2.5-pro-exp-03-25 to gemini-2.5-pro", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-2.5-pro-exp-03-25",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+
+		it("should keep current vertex models as-is", () => {
+			const currentHandler = new VertexHandler({
+				apiModelId: "gemini-2.5-pro",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = currentHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+
+		it("should map gemini-2.0-pro-exp-02-05 to gemini-2.5-pro", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-2.0-pro-exp-02-05",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-pro")
+		})
+
+		it("should map gemini-2.0-flash-thinking-exp-01-21 to gemini-2.5-flash-preview-05-20", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-2.0-flash-thinking-exp-01-21",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-flash-preview-05-20")
+		})
+
+		it("should map gemini-2.5-flash-preview-04-17 to gemini-2.5-flash-preview-05-20", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-2.5-flash-preview-04-17",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-flash-preview-05-20")
+		})
+
+		it("should map gemini-2.5-flash-preview-04-17:thinking to gemini-2.5-flash-preview-05-20", () => {
+			const legacyHandler = new VertexHandler({
+				apiModelId: "gemini-2.5-flash-preview-04-17:thinking",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = legacyHandler.getModel()
+			expect(modelInfo.id).toBe("gemini-2.5-flash-preview-05-20")
+		})
+
+		it("should keep claude models as-is", () => {
+			const claudeHandler = new VertexHandler({
+				apiModelId: "claude-sonnet-4@20250514",
+				vertexProjectId: "test-project",
+				vertexRegion: "us-central1",
+			})
+			const modelInfo = claudeHandler.getModel()
+			expect(modelInfo.id).toBe("claude-sonnet-4@20250514")
+		})
+	})
 })
diff --git a/src/api/providers/gemini.ts b/src/api/providers/gemini.ts
index 5e547edbdc..64b7323b68 100644
--- a/src/api/providers/gemini.ts
+++ b/src/api/providers/gemini.ts
@@ -8,7 +8,7 @@ import {
 } from "@google/genai"
 import type { JWTInput } from "google-auth-library"
 
-import { type ModelInfo, type GeminiModelId, geminiDefaultModelId, geminiModels } from "@roo-code/types"
+import { type ModelInfo, geminiDefaultModelId, geminiModels, mapLegacyGeminiModel } from "@roo-code/types"
 
 import type { ApiHandlerOptions } from "../../shared/api"
 import { safeJsonParse } from "../../shared/safeJsonParse"
@@ -164,8 +164,14 @@ export class GeminiHandler extends BaseProvider implements SingleCompletionHandl
 
 	override getModel() {
 		const modelId = this.options.apiModelId
-		let id = modelId && modelId in geminiModels ? (modelId as GeminiModelId) : geminiDefaultModelId
+		let id = modelId ? mapLegacyGeminiModel(modelId) : geminiDefaultModelId
+
+		if (modelId && modelId !== id) {
+			this.options.apiModelId = id
+		}
+
 		let info: ModelInfo = geminiModels[id]
+
 		const params = getModelParams({ format: "gemini", modelId: id, model: info, settings: this.options })
 
 		// The `:thinking` suffix indicates that the model is a "Hybrid"
diff --git a/src/api/providers/vertex.ts b/src/api/providers/vertex.ts
index 2c077d97b7..dee7f8c062 100644
--- a/src/api/providers/vertex.ts
+++ b/src/api/providers/vertex.ts
@@ -1,4 +1,4 @@
-import { type ModelInfo, type VertexModelId, vertexDefaultModelId, vertexModels } from "@roo-code/types"
+import { type ModelInfo, vertexDefaultModelId, vertexModels, mapLegacyVertexModel } from "@roo-code/types"
 
 import type { ApiHandlerOptions } from "../../shared/api"
 
@@ -14,7 +14,12 @@ export class VertexHandler extends GeminiHandler implements SingleCompletionHand
 
 	override getModel() {
 		const modelId = this.options.apiModelId
-		let id = modelId && modelId in vertexModels ? (modelId as VertexModelId) : vertexDefaultModelId
+		let id = modelId ? mapLegacyVertexModel(modelId) : vertexDefaultModelId
+
+		if (modelId && id && modelId !== id) {
+			this.options.apiModelId = id
+		}
+
 		const info: ModelInfo = vertexModels[id]
 		const params = getModelParams({ format: "gemini", modelId: id, model: info, settings: this.options })
 
diff --git a/webview-ui/src/components/settings/SettingsView.tsx b/webview-ui/src/components/settings/SettingsView.tsx
index 2738b82632..242d007d7b 100644
--- a/webview-ui/src/components/settings/SettingsView.tsx
+++ b/webview-ui/src/components/settings/SettingsView.tsx
@@ -26,6 +26,7 @@ import {
 } from "lucide-react"
 
 import type { ProviderSettings, ExperimentId } from "@roo-code/types"
+import { mapLegacyGeminiModel, mapLegacyVertexModel } from "@roo-code/types"
 
 import { TelemetrySetting } from "@roo/TelemetrySetting"
 
@@ -218,6 +219,38 @@ const SettingsView = forwardRef<SettingsViewRef, SettingsViewProps>(({ onDone, t
 		})
 	}, [])
 
+	const handleLegacyGeminiModelMapping = useCallback(
+		<K extends keyof ProviderSettings>(
+			field: K,
+			previousValue: ProviderSettings[K],
+			value: ProviderSettings[K],
+			provider: string | undefined,
+			updatedApiConfiguration: ProviderSettings,
+		): boolean => {
+			if (field !== "apiModelId" || typeof previousValue !== "string" || typeof value !== "string") {
+				return false
+			}
+
+			let isLegacyMapping = false
+			if (provider === "gemini") {
+				isLegacyMapping = mapLegacyGeminiModel(previousValue) === value
+			} else if (provider === "vertex") {
+				isLegacyMapping = mapLegacyVertexModel(previousValue) === value
+			}
+
+			if (isLegacyMapping && currentApiConfigName) {
+				vscode.postMessage({
+					type: "upsertApiConfiguration",
+					text: currentApiConfigName,
+					apiConfiguration: updatedApiConfiguration,
+				})
+			}
+
+			return isLegacyMapping
+		},
+		[currentApiConfigName],
+	)
+
 	const setApiConfigurationField = useCallback(
 		<K extends keyof ProviderSettings>(field: K, value: ProviderSettings[K], isUserAction: boolean = true) => {
 			setCachedState((prevState) => {
@@ -231,13 +264,24 @@ const SettingsView = forwardRef<SettingsViewRef, SettingsViewProps>(({ onDone, t
 				// This prevents the dirty state when the component initializes and auto-syncs values
 				const isInitialSync = !isUserAction && previousValue === undefined && value !== undefined
 
-				if (!isInitialSync) {
+				const updatedApiConfiguration = { ...prevState.apiConfiguration, [field]: value }
+
+				const isLegacyMapping = handleLegacyGeminiModelMapping(
+					field,
+					previousValue,
+					value,
+					prevState.apiConfiguration?.apiProvider,
+					updatedApiConfiguration,
+				)
+
+				if (!isInitialSync && !isLegacyMapping) {
 					setChangeDetected(true)
 				}
-				return { ...prevState, apiConfiguration: { ...prevState.apiConfiguration, [field]: value } }
+
+				return { ...prevState, apiConfiguration: updatedApiConfiguration }
 			})
 		},
-		[],
+		[handleLegacyGeminiModelMapping],
 	)
 
 	const setExperimentEnabled: SetExperimentEnabled = useCallback((id: ExperimentId, enabled: boolean) => {
diff --git a/webview-ui/src/components/ui/hooks/useSelectedModel.ts b/webview-ui/src/components/ui/hooks/useSelectedModel.ts
index 75a4a968ad..24b0e72f6c 100644
--- a/webview-ui/src/components/ui/hooks/useSelectedModel.ts
+++ b/webview-ui/src/components/ui/hooks/useSelectedModel.ts
@@ -40,6 +40,8 @@ import {
 	sambaNovaDefaultModelId,
 	doubaoModels,
 	doubaoDefaultModelId,
+	mapLegacyGeminiModel,
+	mapLegacyVertexModel,
 	internationalZAiDefaultModelId,
 	mainlandZAiDefaultModelId,
 	internationalZAiModels,
@@ -202,12 +204,14 @@ function getSelectedModel({
 			return { id, info: baseInfo }
 		}
 		case "vertex": {
-			const id = apiConfiguration.apiModelId ?? vertexDefaultModelId
+			const rawId = apiConfiguration.apiModelId ?? vertexDefaultModelId
+			const id = mapLegacyVertexModel(rawId)
 			const info = vertexModels[id as keyof typeof vertexModels]
 			return { id, info }
 		}
 		case "gemini": {
-			const id = apiConfiguration.apiModelId ?? geminiDefaultModelId
+			const rawId = apiConfiguration.apiModelId ?? geminiDefaultModelId
+			const id = mapLegacyGeminiModel(rawId)
 			const info = geminiModels[id as keyof typeof geminiModels]
 			return { id, info }
 		}