US Regional Routing
Regional routing refers to the physical or geographic location where data is processed. This page explains Tuna's approach to US regional routing.
US Regional Routing at No Additional Charge
US regional routing is included in Tuna's model prices. It is available to all users without a separate request or an enterprise plan.
Some providers charge a premium for US-only or regional inference processing. This survey of some providers compares their published prices at the time of writing in 2026:
| Provider | Published regional processing price |
|---|---|
| Tuna | No additional charge (0%) US regional routing is the default for all models.[source] |
| OpenAI | +10% for regional processing on eligible models released on or after March 5, 2026. Requires contacting sales.[source] |
| Anthropic | +10% for US-only inference (inference_geo: "us") on Claude 4.6 and later.[source] |
| xAI (Grok) | +10% for US-only inference through us.api.x.ai on Grok 4.7 and Grok 4.6.[source] |
| Amazon Bedrock | +10% for regional inference (including US) on Claude 4.5 and later.[source] |
| Google Cloud | +10% for US multi-region inference on Gemini 3.8 Flash and Claude 4.5 and later.[source][source] |
| Fireworks | +10% to +50% for US-only models (10% through OpenRouter, 50% directly, with exceptions).[source] |
Why US Regional Routing?
For some customers (such as financial institutions, healthcare organizations, and enterprises handling confidential information), US regional routing is necessary. Tuna was built for those customers from the start.
Tuna uses GPU servers in US data centers for AI inference. Serving inference from the United States is part of the company's long-term business strategy to maintain security and reduce unforeseen geopolitical risks. US hosting costs more, but the security and geopolitical benefits are worth the additional cost.
Tuna Inference, Inc. is a US company registered in the state of Delaware, with majority natural person ownership held by US citizens.
US regional routing and US ownership do not override applicable laws. The laws of your own country may still apply to your use of Tuna and to the data you send. Tuna serves non-US customers and may also be subject to non-US laws when applicable.
The tuna-us/ Model Prefix Guarantee
For a model id beginning with tuna-us/, GPU inference is limited to data centers on land physically located in the United States. Tuna uses US ground-based data centers and currently has no plans to use satellite data centers.
The guarantee covers inference content, including prompts, uploaded images, model replies, and the associated KV caches. It applies to HTTPS termination, Tuna's inference backend services, and GPU inference. The inference backend receives customer requests, routes them to GPU servers, and returns the responses.
| Data | Location |
|---|---|
| Inference HTTPS termination and backend processing | Google Cloud, US region |
| Prompts, uploaded images, and replies during GPU inference | US data centers |
| Temporary KV caches, including encrypted SSD offload | US data centers |
| Prompts and replies retained after processing | Not retained (ZDR) |
| Management API and account, usage, and billing records | Not covered by US regional routing (see below) |
Using US Regional Routing
Send inference requests to api-us.tuna.ai with a tuna-us/ model id, such as tuna-us/moonshotai/kimi-k3-ultrafast. No project-region setting or sales approval is needed. All of Tuna's current model endpoints use this prefix.
The code examples in these docs use tuna-us/example-lab/example-model-id as a placeholder. Choose an available id from List Model Endpoints when making a request.
Data Residency
Under Zero Data Retention (ZDR), Tuna does not retain your prompts or model replies. Temporary KV caches reside on GPU servers in US data centers, including any encrypted SSD offload. See KV Cache for how these caches are handled.
Management API and Account Data
Tuna's management API handles user accounts and routes through the edge without US regional routing. Its HTTPS connections may terminate outside the United States. This API does not carry inference prompts. Inference requests use the separate api-us.tuna.ai endpoint described above.
Account, usage, and billing records are outside the inference regional routing guarantee. Tuna uses Stripe for payments, Metronome for usage billing, and WorkOS for organization sign-in. These services have their own data-handling policies and residency arrangements. Usage billing records do not contain prompts or model replies. See Billing and Organizations and projects for details.
HTTPS Termination
HTTPS connections to api-us.tuna.ai terminate on Google Cloud servers in the United States. Requests remain encrypted in transit until they reach that US endpoint, where TLS decryption takes place. Traffic between Tuna's inference backend services and GPU servers is also encrypted.
Requests to api-us.tuna.ai do not route through Cloudflare.
Infrastructure Providers
Tuna runs its inference backend services on Google Cloud in a US region. Tuna runs inference on GPU servers hosted in US data centers. Both the inference backend and GPU processing are covered by the regional routing guarantee.
When Encrypted Traffic May Travel Outside the US
US regional routing determines where Tuna processes inference content. The internet path between your app and Tuna can still cross borders, even when both ends of a connection are in the United States. HTTPS encryption prevents network operators in those countries from reading your prompts and replies. Requests are decrypted only when they reach the Google Cloud endpoint in the United States.
Illustrative examples include (but are not limited to):
- A request from outside the United States. The request travels over HTTPS from the customer's country to Google Cloud servers in the United States, where the connection terminates and the request is decrypted.
- A connection from Alaska. Depending on the internet provider's route, traffic between Alaska and the contiguous United States may pass through Canada.
- Satellite internet connection (such as through airplane Wi-Fi or Starlink). Packets travel to a satellite and back to a ground station. A connection can start and end in the United States while part of its path is in orbit.
- An image sent as a URL. When an inference request instructs Tuna to download publicly available content from a URL, such as an image URL, Tuna retrieves that content from the server hosting it. The server hosting that publicly available content may be outside the United States.
Privacy Policy and Terms of Service
These docs are for informational purposes only. Tuna's Privacy Policy and Terms of Service take precedence over these docs if there is a conflict.