diff --git a/apps/web/src/lib/ai-gateway/providers/provider-definitions.ts b/apps/web/src/lib/ai-gateway/providers/provider-definitions.ts
index 6588d1ec04..b151f2a5ae 100644
--- a/apps/web/src/lib/ai-gateway/providers/provider-definitions.ts
+++ b/apps/web/src/lib/ai-gateway/providers/provider-definitions.ts
@@ -75,7 +75,7 @@ export default {
     apiKey: getEnvVariable('VERCEL_AI_GATEWAY_API_KEY'),
     supportedChatApis: ['chat_completions', 'messages', 'responses'],
     async transformRequest(context) {
-      applyVercelSettings(context.model, context.request, context.userByok);
+      await applyVercelSettings(context.model, context.request, context.userByok);
     },
   },
 } as const satisfies Record<string, Provider>;
diff --git a/apps/web/src/lib/ai-gateway/providers/vercel/index.test.ts b/apps/web/src/lib/ai-gateway/providers/vercel/index.test.ts
index 5efa239edc..e0877f1bc0 100644
--- a/apps/web/src/lib/ai-gateway/providers/vercel/index.test.ts
+++ b/apps/web/src/lib/ai-gateway/providers/vercel/index.test.ts
@@ -1,6 +1,8 @@
 import { describe, it, expect } from '@jest/globals';
 import {
+  convertProviderOptions,
   getAnthropicProviderOptionsForVercel,
+  getVercelInferenceProvidersExcludingIgnored,
   hasCompatibleVercelInferenceProvider,
   passesVercelRoutingPercentage,
 } from '@/lib/ai-gateway/providers/vercel';
@@ -73,6 +75,59 @@ describe('hasCompatibleVercelInferenceProvider', () => {
   });
 });
 
+describe('getVercelInferenceProvidersExcludingIgnored', () => {
+  it('returns available providers minus translated ignored providers', () => {
+    expect(
+      getVercelInferenceProvidersExcludingIgnored(['amazon-bedrock'], undefined, [
+        'anthropic',
+        'bedrock',
+        'vertex',
+      ])
+    ).toEqual(['anthropic', 'vertex']);
+  });
+
+  it('intersects the available providers with only before excluding ignored providers', () => {
+    expect(
+      getVercelInferenceProvidersExcludingIgnored(
+        ['google-vertex'],
+        ['amazon-bedrock', 'google-vertex', 'openai'],
+        ['anthropic', 'bedrock', 'vertex']
+      )
+    ).toEqual(['bedrock']);
+  });
+
+  it('returns an empty list when all available providers are ignored', () => {
+    expect(
+      getVercelInferenceProvidersExcludingIgnored(['anthropic', 'amazon-bedrock'], undefined, [
+        'anthropic',
+        'bedrock',
+      ])
+    ).toEqual([]);
+  });
+});
+
+describe('convertProviderOptions', () => {
+  it('emits only available non-ignored providers without changing provider.only', () => {
+    const request: GatewayRequest = {
+      kind: 'chat_completions',
+      body: {
+        model: 'anthropic/claude-sonnet-4.5',
+        messages: [{ role: 'user', content: 'hello' }],
+        provider: {
+          only: ['anthropic', 'amazon-bedrock'],
+          ignore: ['amazon-bedrock'],
+        },
+      },
+    };
+
+    const provider = request.body.provider;
+    const providerOptions = convertProviderOptions(request, ['anthropic', 'bedrock', 'vertex']);
+
+    expect(providerOptions.gateway?.only).toEqual(['anthropic']);
+    expect(provider?.only).toEqual(['anthropic', 'amazon-bedrock']);
+  });
+});
+
 describe('passesVercelRoutingPercentage', () => {
   it('never passes at 0% and always passes at 100%', () => {
     for (let seed = 0; seed < 1_000; seed++) {
diff --git a/apps/web/src/lib/ai-gateway/providers/vercel/index.ts b/apps/web/src/lib/ai-gateway/providers/vercel/index.ts
index 9df72efcea..c9676d8038 100644
--- a/apps/web/src/lib/ai-gateway/providers/vercel/index.ts
+++ b/apps/web/src/lib/ai-gateway/providers/vercel/index.ts
@@ -52,6 +52,21 @@ export function hasCompatibleVercelInferenceProvider(
   );
 }
 
+export function getVercelInferenceProvidersExcludingIgnored(
+  ignoredProviders: string[],
+  onlyProviders: string[] | undefined,
+  vercelInferenceProviders: string[]
+) {
+  const ignored = new Set(ignoredProviders.map(openRouterToVercelInferenceProviderId));
+  const only = onlyProviders
+    ? new Set(onlyProviders.map(openRouterToVercelInferenceProviderId))
+    : null;
+
+  return vercelInferenceProviders.filter(
+    provider => !ignored.has(provider) && (!only || only.has(provider))
+  );
+}
+
 export function passesVercelRoutingPercentage(randomSeed: string, routingPercentage: number) {
   const routingSeed = 'vercel_routing_' + randomSeed;
   const wholePercentageBucket = getRandomNumber(routingSeed, 100);
@@ -66,13 +81,6 @@ export async function shouldRouteToVercel(
   request: GatewayRequest,
   randomSeed: string
 ) {
-  if ((request.body.provider?.ignore?.length ?? 0) > 0) {
-    console.debug(
-      '[shouldRouteToVercel] not routing to Vercel because of unsupported provider options'
-    );
-    return false;
-  }
-
   if (!kiloExclusiveModel?.flags.includes('vercel-routing') && isDeepseekModel(requestedModel)) {
     // https://kilo-code.slack.com/archives/C0A4SA041DE/p1781743079721409
     console.debug(
@@ -97,11 +105,32 @@ export async function shouldRouteToVercel(
     return false;
   }
 
-  const only = request.body.provider?.only;
-  if (only) {
+  const provider = request.body.provider;
+  if (provider && (provider.only || provider.ignore?.length)) {
+    const { only, ignore } = provider;
     const vercelInferenceProviders =
       await getCachedVercelInferenceProviderIdsForModel(vercelModelId);
-    if (!hasCompatibleVercelInferenceProvider(only, vercelInferenceProviders)) {
+
+    if (ignore?.length) {
+      if (!vercelInferenceProviders) {
+        console.debug(
+          '[shouldRouteToVercel] not routing to Vercel because inference provider data is unavailable'
+        );
+        return false;
+      }
+
+      const effectiveOnly = getVercelInferenceProvidersExcludingIgnored(
+        ignore,
+        only,
+        vercelInferenceProviders
+      );
+      if (effectiveOnly.length === 0) {
+        console.debug(
+          '[shouldRouteToVercel] no inference providers remain after applying provider preferences'
+        );
+        return false;
+      }
+    } else if (only && !hasCompatibleVercelInferenceProvider(only, vercelInferenceProviders)) {
       console.debug(
         '[shouldRouteToVercel] none of the requested inference providers are available on Vercel'
       );
@@ -112,11 +141,28 @@ export async function shouldRouteToVercel(
   return true;
 }
 
-function convertProviderOptions(requestToMutate: GatewayRequest): VercelProviderConfig {
+export function convertProviderOptions(
+  requestToMutate: GatewayRequest,
+  vercelInferenceProviders: string[] | null
+): VercelProviderConfig {
   const provider = requestToMutate.body.provider;
+  const only = (() => {
+    if (!provider?.ignore?.length) {
+      return provider?.only?.map(openRouterToVercelInferenceProviderId);
+    }
+    if (!vercelInferenceProviders) {
+      throw new Error('Vercel inference provider data became unavailable during request transform');
+    }
+    return getVercelInferenceProvidersExcludingIgnored(
+      provider.ignore,
+      provider.only,
+      vercelInferenceProviders
+    );
+  })();
+
   return {
     gateway: {
-      only: provider?.only?.map(p => openRouterToVercelInferenceProviderId(p)),
+      only,
       order: provider?.order?.map(p => openRouterToVercelInferenceProviderId(p)),
       zeroDataRetention: provider?.zdr,
       disallowPromptTraining: provider?.data_collection === 'deny' || undefined,
@@ -180,12 +226,13 @@ export function getVercelInferenceProviderConfigForUserByok(
   return [key, list];
 }
 
-export function applyVercelSettings(
+export async function applyVercelSettings(
   requestedModel: string,
   requestToMutate: GatewayRequest,
   userByok: BYOKResult[] | null
 ) {
-  requestToMutate.body.model = mapModelIdToVercel(requestedModel);
+  const vercelModelId = mapModelIdToVercel(requestedModel);
+  requestToMutate.body.model = vercelModelId;
 
   if (userByok) {
     if (userByok.length === 0) {
@@ -207,7 +254,13 @@ export function applyVercelSettings(
       },
     };
   } else {
-    requestToMutate.body.providerOptions = convertProviderOptions(requestToMutate);
+    const vercelInferenceProviders = requestToMutate.body.provider?.ignore?.length
+      ? await getCachedVercelInferenceProviderIdsForModel(vercelModelId)
+      : null;
+    requestToMutate.body.providerOptions = convertProviderOptions(
+      requestToMutate,
+      vercelInferenceProviders
+    );
   }
 
   if (requestToMutate.body.providerOptions) {