VPC endpoints pricing: what to model (interface vs gateway endpoints)

VPC endpoints are a common way to reduce NAT Gateway traffic and keep AWS-service access private. Cost modeling is simple if you separate two concepts: endpoint-hours and data processed (GB), plus any data transfer boundaries in your architecture.

What to model (interface vs gateway endpoints)

Interface endpoints: endpoint-hours (endpoints x AZs x hours) and sometimes a per-GB processing fee.
Gateway endpoints: a different cost model depending on service; treat them separately.
Transfer boundaries: cross-AZ/cross-region paths can create separate transfer line items.

The same "private access" goal can be achieved with different endpoint types. Always model the endpoint line item and the transfer path together.

Interface vs gateway endpoints: decision points

Interface endpoints (PrivateLink): great when you need private access to many AWS services, but they add endpoint-hours per AZ and can multiply quickly across environments.
Gateway endpoints: a different mechanism with a different cost model. Treat them separately and verify which services in your architecture can use them.
Path matters: if clients in one AZ consistently talk to endpoints in another AZ, you can introduce cross-AZ transfer even if the endpoint line item looks correct.

Fast estimate (baseline + scenario)

Use VPC Interface Endpoint Cost Calculator for a first-pass estimate of endpoint-hours + per-GB processing.

Baseline: current NAT GB processed and current endpoint inventory (if any).
Scenario: endpoints added + NAT traffic reduced + any expected cross-AZ path changes.

Worked estimate template (copy/paste)

Endpoint-hours = endpoints * AZs per endpoint * hours/month
Endpoint GB processed = GB/month expected to flow through endpoints
Endpoint cost = hourly baseline + per-GB processing (if applicable)

Quick sanity check: if you add many endpoints across 3 AZs, the hourly baseline can dominate even when GB processed is modest. Model the hours first, then refine GB.

NAT break-even checklist

How much NAT GB processed is actually AWS-service traffic that can move to endpoints?
How many endpoints will you deploy (and in how many AZs) across prod/staging/dev?
Will endpoint routing change traffic locality (cross-AZ) or keep it AZ-local?
Do you need endpoints everywhere, or only in a subset of VPCs and accounts?

Common pitfalls

Forgetting that interface endpoints scale with the number of AZs you use.
Moving traffic across AZs or regions and creating new transfer charges.
Assuming endpoints replace NAT costs without validating the traffic mix.
Counting endpoints once while they exist in multiple VPCs and environments.

How to validate the pricing model

Reconcile endpoint-hours in billing against endpoints * AZs * hours.
Spot-check the top destinations and verify they are the services you intended to route through endpoints.
After rollout, compare NAT GB processed and endpoint GB processed as a before/after sanity check.

Sources

A practical AWS network cost hub: how to model NAT Gateway, VPC endpoints/PrivateLink, and cross-AZ/cross-region data transfer. Includes formulas, break-even workflow, and a troubleshooting checklist.

NAT Gateway vs VPC endpoints cost: when PrivateLink wins

Compare NAT Gateway vs VPC endpoints (Interface/Gateway endpoints) cost: model gateway-hours + GB processed versus endpoint-hours + per-GB, estimate how much NAT traffic endpoints remove, and avoid transfer surprises.

API Gateway pricing: what to model (requests + transfer)

A practical API Gateway pricing checklist: request charges, data transfer, and the add-ons that can show up on the bill.

API Gateway cost optimization: reduce requests, bytes, and log spend

A practical playbook to reduce API Gateway spend: identify the dominant driver (requests, transfer, or logs), then apply high-leverage fixes with a validation checklist.

API Gateway vs ALB vs CloudFront cost: what to compare (requests, transfer, add-ons)

A practical cost comparison of API Gateway, Application Load Balancer (ALB), and CloudFront. Compare request pricing, data transfer, caching impact, WAF, logs, and the hidden line items that change the answer.

AWS cost checklist: model the drivers that actually move the bill

A practical AWS cost checklist for planning and reviews: define scope, identify top cost drivers (requests, GB, GB-month, hours), and avoid the common blind spots (data transfer, logs, and cross-AZ).

Related calculators

Data Egress Cost Calculator

Estimate monthly egress spend from GB transferred and $/GB pricing.

API Response Size Transfer Calculator

Estimate monthly transfer from request volume and average response size.

VPC Data Transfer Cost Calculator

Estimate data transfer spend from GB/month and $/GB assumptions.

Cross-region Transfer Cost Calculator

Estimate monthly cross-region transfer cost from GB transferred and $/GB pricing.

RPS to Monthly Requests Calculator

Estimate monthly request volume from RPS, hours/day, and utilization.

API Request Cost Calculator

Estimate request-based charges from monthly requests and $ per million.

FAQ

Do VPC endpoints always save money?

Not always. Endpoints add their own hourly fees (and sometimes per-GB processing), but they can reduce NAT GB processed and improve security by keeping traffic private. Model your traffic mix to find break-even.

What's the biggest multiplier for endpoint cost?

Availability Zones. Interface endpoints are deployed per AZ. If you attach endpoints in 3 AZs, your endpoint-hours are roughly 3x compared to 1 AZ.

Are gateway endpoints billed the same way as interface endpoints?

No. Gateway endpoints differ by service and can have a different cost model. The key is to treat endpoints as their own line items and model your actual traffic path.

Last updated: 2026-01-27