🌎 AWS Regions and Availability Zones: Why Your Instance Disappeared

What a region and an Availability Zone are on AWS, which regions are on by default and which you must switch on, zone names against zone IDs, and the beginner mistake of looking at the wrong region

💡 How this page was written. From AWS's documentation ("AWS Regions" and "AZ IDs" in the Global Infrastructure guide, and the EC2 user guide), read on 6 October 2026. Nothing here was run on an account. The region list grows, so the numbers are a snapshot: the current list is on the AWS "Regions and Availability Zones" documentation page. The same ideas on Azure are on the Azure regions page.

The short version

Regions

Each region has a code (what you type in commands) and a name (what the console shows). Some examples from AWS's list:

Each region sits in a geography (a country or area), which matters if the data must stay somewhere: choose a region whose geography matches the rule.

Two kinds of account see different regions: AWS GovCloud (US) accounts get the two GovCloud regions, and Amazon AWS (China) accounts get the Beijing and Ningxia regions. You cannot use one from the other kind of account.

Opt-in regions: some are switched off

This surprises people. Regions introduced after March 20, 2019 are disabled until you enable them. The older ones are on by default. From AWS's list:

To enable one: console AWS Global View, then Regions and Zones, select the region and choose Enable Region, or the Billing and Cost Management console. From the CLI (needs an account, from the documentation, not run here):

aws account list-regions --region-opt-status-contains ENABLED_BY_DEFAULT ENABLED --query "Regions[*].RegionName"
aws account get-region-opt-status --region-name af-south-1
aws ec2 describe-regions --output table

How to choose

  1. Services. Check that the services and features you need exist in that region: the "AWS Services by Region" page shows it. New services often start in a few regions.
  2. Latency. Close to your users, or to you for learning.
  3. Law and compliance. Choose by geography when the data must stay inside a country or a bloc.
  4. Price. Prices differ by region, so compare on the pricing pages (do not assume the biggest region is the cheapest, or the other way around).

For learning: one region, and stay in it. Resources in different regions are separate, and moving data between regions costs money.

The beginner mistake: "my instance disappeared"

The console shows one region at a time, in the selector in the top bar. You create an instance in Ohio, open the console later with Tokyo selected, and the instance list is empty. Nothing is lost: you are looking at the wrong region. Three habits that fix it:

Availability Zones

Each region has several AZs, and AZs in a region are connected by fast private links. The details that matter:

Zone names and zone IDs

The AZ names you see (us-east-1a, us-east-1b) are labels. For many years AWS mapped the labels to physical zones separately for every account, so that not everybody picked a. From AWS's documentation:

See the mapping for your account (from the documentation, not run here):

aws ec2 describe-availability-zones --query "AvailabilityZones[].{Name:ZoneName,ID:ZoneId}" --output table

AWS's example output for US East (Ohio) pairs use2-az1 with us-east-2a, use2-az2 with us-east-2b and use2-az3 with us-east-2c. Add --region NAME for another region.

Two more words you will see: Local Zones (small extensions of a region closer to a city) and Outposts (AWS hardware in your own building). Both are outside this page.

Side by side with Azure

Common mistakes

The cheat sheet

← Creating an AWS Account: Root User, Plans and the First Hour · ↑ All tutorials · AWS Services: A Map for People Who Know Linux →

© 2026 TechCommune. All rights reserved.
"Nothing is lost in AWS. It is just in a region you are not looking at."