Practical guide
NAT Gateway pricing: separate gateway hours from processed data
understand AWS NAT Gateway monthly cost. Includes a worked example, calculator scope, and practical questions.
Updated · Sources checked
Why an idle NAT gateway can still cost money
NAT Gateway has a time component as well as a processed-data component. A low-traffic environment can therefore have a meaningful network bill even when few bytes pass through it. Internet data transfer is a separate charge category; the NAT processing subtotal is not an egress estimate.
Count billable gateways or Availability Zone coverage first, then total data processed over the billing period. Regional NAT billing follows active Availability Zones, so one regional resource must not automatically be treated as one billable gateway-hour stream.
Worked example: a three-zone application
Consider three continuously billable gateway equivalents, each operating for a hypothetical 730-hour month. They generate 3 × 730 = 2,190 gateway-hours. Suppose combined processed traffic is 900 GB.
Let H be the matching price per gateway-hour and P the price per processed GB. The modeled subtotal is 2,190H + 900P. Do not multiply the 900 GB by three again if it already represents all gateways. That common duplication inflates the data-processing forecast.
Now hold traffic constant and compare two gateway equivalents: the subtotal becomes 1,460H + 900P. The arithmetic difference is 730H, but changing topology can introduce cross-zone traffic and alter availability. The smaller subtotal alone does not justify that architecture change.
Prepare trustworthy inputs
Use billing usage types or consistently scoped network metrics for the traffic total. A downloaded object and the application response are not always the same traffic quantity. Retries, software updates, container image pulls, and background agents can materially change processed bytes.
The calculator uses an official US East example rate and whole monthly hours. It excludes public IPv4 and standard data-transfer charges. AWS rounds partial gateway-hours up, so many short-lived gateways need a more detailed hour calculation than a single continuous resource.
Frequently asked questions
Is NAT data processing included in internet egress? No. Keep the two components separate when the same traffic incurs both.
Will reducing data remove the hourly charge? No. It reduces the variable component. The billable gateway must no longer be provisioned to remove its ongoing time charge.
Calculate your scenario
Use the nat gateway cost calculator. Keep the displayed region, pricing date, billing units, and exclusions alongside your result. The arithmetic examples above illustrate usage or explicitly hypothetical rates; they are not AWS quotes.
Source
Billing structure checked against official AWS documentation on September 6, 2026.