Opening an enterprise AWS monthly billing report frequently reveals an unwelcome surprise: under the Amazon Virtual Private Cloud (VPC) line item, charges for Managed NAT Gateways routinely surpass the cost of production compute instances. Unlike EC2 or RDS instances that deliver tangible computing power, NAT Gateway fees represent a toll for routing your own outbound network traffic.
Why Is AWS NAT Gateway Data Processing So Expensive?
Our cloud FinOps practice audited network traffic architectures across large Kubernetes clusters to eliminate unnecessary NAT transit charges.
Deploying Free VPC Gateway Endpoints
AWS provides VPC Gateway Endpoints for Amazon S3 and DynamoDB at zero cost. By adding an S3 Gateway Endpoint to your VPC route tables, all traffic bound for S3 buckets bypasses NAT Gateways entirely and routes directly across AWS private network backbones with zero data processing fees.
| NAT Routing Strategy | Hourly Base Cost | Data Processing Cost per GB | FinOps Savings Impact |
|---|---|---|---|
| AWS Managed NAT Gateway | $0.045 / hour (~$32.40/mo per AZ) | $0.045 per GB processed ($45/TB) | Standard expensive AWS default |
| VPC Gateway Endpoints (S3/Dynamo) | $0.00 (100% Free by AWS) | $0.00 per GB (100% Free) | Slashes 60%–80% of internal data egress instantly |
| Open-Source fck-nat (t4g.nano) | $0.0042 / hour (~$3.02/mo) | $0.00 per GB processed | Cuts NAT gateway costs by 90%+ on dev/staging |
| Self-Managed iptables EC2 (t4g.medium) | $0.0336 / hour (~$24.20/mo) | $0.00 per GB processed | High throughput without per-GB data penalty |
| Dual-AZ Redundant Managed NAT | $64.80/mo fixed base | $45 per TB processed | High monthly cost for unoptimized data flows |
Never route internal AWS service communication through a managed NAT Gateway. Configure free VPC Gateway Endpoints for Amazon S3 and DynamoDB immediately, and evaluate open-source alternatives like fck-nat on Graviton instances to eliminate the predatory $0.045/GB data processing tax.