Explanation
Why the waste happens and who it affects.
When large volumes of traffic flow through the gateway - particularly during batch processing, frequent software updates, or hybrid cloud integrations - the per-GB charges accumulate rapidly. In some cases, replacing a managed NAT Gateway with a self-managed NAT instance can substantially reduce costs, provided that the organization is prepared to operate and maintain the alternative solution.
Billing model
The pricing dimensions that drive this cost.
NAT Gateway pricing includes:
- Hourly cost per deployed gateway per Availability Zone
- Per-GB data processing fees for all traffic routed through the gateway
These charges apply regardless of usage pattern and can scale significantly in high-throughput environments.
How to detect
6 checks to find it in your estate.
- Identify NAT Gateways with consistently high data processing volumes over the lookback period
- Review per-GB transfer charges to assess whether NAT Gateway usage represents a significant portion of total networking costs
- Determine whether traffic patterns are driven by expected workload behavior or architectural inefficiencies
- Evaluate whether alternative designs - such as VPC endpoints or NAT instances-could reduce data processing costs
- Consider that replacing a managed NAT Gateway with a self-managed NAT instance introduces operational overhead (e.g., scaling, patching, monitoring).
- Confirm whether the potential savings outweigh the additional management effort
How to fix
How to remove the waste.
In environments with large volumes of outbound traffic, consider replacing the managed NAT Gateway with a self-managed NAT instance to reduce per-GB data processing costs. Alternatively, evaluate architectural changes to reduce or avoid NAT usage altogether - such as using VPC endpoints for AWS service access. Weigh the trade-offs between cost savings and the operational complexity of managing your own NAT infrastructure.
Documentation
Vendor references for pricing and configuration.