AI & Machine Learning · Engineering, IT & AI

Should you build or buy LLM / AI Gateway & Cost Control?

LLM / AI Gateway & Cost Control software acts as a proxy layer between applications and language model APIs — handling request routing, model fallback chains, cost tracking, rate limiting, and semantic caching in one place. It gives engineering teams a single control point for managing which models different applications use, at what cost, and with what governance policies applied.

The build-vs-buy decision for LLM / AI Gateway & Cost Control turns on whether a support relationship and managed control plane justify the subscription when LiteLLM is open-source, production-proven at thousands of deployments, and covers the routing and cost-tracking use case for free; your scale and governance requirements decide it.

Domain
AI & Machine Learning
Function
Engineering, IT & AI
Industries
Cross-industry

Last assessed June 2026 · re-scored quarterly via The Continuum.

Build it, buy it, or bridge?

Build it Buy it Bridge (buy, then extend)
Cost shape LiteLLM self-hosted is free; enterprise tier is $2-3.5K/mo flat vs per-request managed pricing Portkey or TrueFoundry pricing scales with usage; compounds at high traffic volume LiteLLM self-hosted for core routing; vendor control plane for analytics and support
Time to value LiteLLM running with basic routing and cost dashboards in hours Managed gateway operational with support contract same-day Vendor for immediate deployment with LiteLLM migration path as volume grows
Differentiation captured Routing rules and cost policies encode AI governance decisions — emerging strategic value Governance policies are yours but the infrastructure is generic vendor default Vendor infrastructure with organizational routing rules and governance policies
AI feasibility today LiteLLM is the de facto self-hosted standard with 1,600+ model coverage and documented production deployments Vendors add managed ops, support relationships, and compliance documentation on the LiteLLM foundation LiteLLM OSS foundation with vendor wrapper for enterprise compliance requirements
Who it fits Any team with basic infrastructure capacity and meaningful LLM request volume Teams needing vendor accountability, compliance documentation, or a managed ops relationship Enterprise teams wanting LiteLLM's coverage with vendor-managed reliability guarantees

The B4 call

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When building LLM / AI Gateway & Cost Control makes sense

LiteLLM is the fact on the ground that shapes this decision. It's open-source, covers 1,600+ models, handles fallback chains, semantic caching, and cost tracking, and has documented production deployments across a wide range of team sizes. The self-hosted build is not a from-scratch engineering project — it's a configuration and deployment exercise. The build case gets more interesting as AI governance becomes a real organizational function. Routing rules and cost policies increasingly encode decisions about which models are approved for which use cases and by which teams. Owning that layer means iterating on governance without depending on vendor support ticket timelines. Managed gateway pricing tends to scale linearly with traffic, while self-hosted fixed costs become more favorable at volume. Teams doing meaningful LLM usage find the break-even comes earlier than it looks.

When buying LLM / AI Gateway & Cost Control makes sense

Buying from Portkey, TrueFoundry, or a managed LiteLLM wrapper makes sense when the team wants vendor accountability for uptime, compliance documentation that procurement can review, or a support relationship for an infrastructure component that handles production traffic. For teams where LLM gateway infrastructure is not a core competency and the operational risk of self-hosting a proxy layer feels disproportionate to the workload, managed options are worth the premium. The practical consideration is that many managed gateway providers are effectively running LiteLLM with a control plane and a support contract on top — teams should understand what they're actually buying before committing to per-request pricing that scales linearly with usage.

LiteLLM is the fact on the ground that shapes this decision. It's open-source, covers 1,600+ models, handles fallback chains and semantic caching, and has documented production deployments across a wide range of team sizes. Managed offerings from Portkey and TrueFoundry add a control plane and a support relationship on top of that foundation, which is worth real money to teams that don't want to operate infra or need vendor accountability for uptime.

The build case gets more interesting as AI governance becomes a real function. Routing rules and cost policies increasingly encode decisions about which models are approved for which use cases, and owning that layer means you can iterate on governance without filing support tickets. Managed gateway pricing tends to scale linearly with traffic, while self-hosted fixed costs become more favorable at volume. Teams doing early LLM experimentation rarely feel the difference; teams at meaningful scale start to.

Representative vendors

PortkeyLiteLLM / BerriAI and 3 more, scored in B4 Pro

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Frequently asked

What is LLM / AI Gateway & Cost Control?
LLM / AI Gateway & Cost Control software acts as a proxy layer between applications and language model APIs — handling routing, model fallback chains, cost tracking, rate limiting, and semantic caching in one place, giving teams a single control point for managing model usage and cost.
When does building LLM / AI Gateway & Cost Control make sense?
Building with self-hosted LiteLLM makes sense for most teams — it covers 1,600+ models, handles routing and cost tracking out of the box, is free, and has thousands of documented production deployments; the build reduces to configuration and deployment.
When does buying LLM / AI Gateway & Cost Control make sense?
Buying makes sense when vendor accountability, compliance documentation, or a managed ops relationship for production infrastructure is worth the premium over self-hosting — particularly for teams where gateway operations are not a core focus.
What are the main LLM / AI Gateway & Cost Control vendors?
Representative vendors include Portkey, LiteLLM / BerriAI, Helicone, Zuplo AI Gateway. B4 Pro scores the full set.
How does an AI gateway differ from semantic caching?
An AI gateway handles the full request lifecycle — routing, fallback, rate limiting, cost tracking, and policy enforcement across all LLM calls. Semantic caching is one specific capability that may be bundled into a gateway, but a gateway's scope covers governance and reliability across the entire model API layer, not just cost reduction through response reuse.
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