# Unnecessary Additional Regions on Cosmos DB Accounts Canonical: https://www.pointfive.co/efficiency-hub/inefficiencies/unnecessary-additional-regions-on-cosmos-db-accounts Cosmos DB makes global replication a checkbox: regions can be added to an account at any time, and every container's provisioned throughput and every... By: PointFive Updated: 2026-09-28 [Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) The short version Cosmos DB makes global replication a checkbox: regions can be added to an account at any time, and every container's provisioned throughput and every GB of data is then reserved and stored again in each region. PointFive Research Cloud cost research at PointFive Azure service [Azure Cosmos DB](https://www.pointfive.co/efficiency-hub/cloud-services/azure-cosmos-db) Category [Databases](https://www.pointfive.co/efficiency-hub/service-category/databases) Reference CER-0441 Type Overprovisioned Resource ## Explanation Why the waste happens and who it affects. An account with two extra read regions pays three times the throughput and three times the storage of a single-region account, whether or not any client ever reads from those regions. Extra regions accumulate when production templates with geo-redundancy or multi-region writes are reused for development, test and staging accounts, when a region added for a past latency goal or a migration is never removed, or when a disaster recovery design is set once and not revisited. Microsoft's multi-region cost guidance tells teams to monitor consumed throughput per region and add or remove regions on demand, and calls under-utilized read regions inefficient. ## Billing model The pricing dimensions that drive this cost. Regional throughput RU/s configured on databases and containers is reserved in every region of the account, so the hourly total is RU/s times the number of regions Regional storage Data and index storage is billed in each region that holds a replica Multi-region writes Every region becomes writable and throughput is billed at the multi-region write rate Region removal Regions can be removed at any time; in single-region write mode the write region must be failed over first ## How to detect 5 checks to find it in your estate. - List Cosmos DB accounts with more than one entry in properties.locations (Azure Resource Graph type microsoft.documentdb/databaseaccounts), and flag non-production accounts and accounts with enableMultipleWriteLocations set to true - For each secondary region, chart Total Requests and Total Request Units split by Region over 30 days; read regions that serve almost no client traffic beyond replication are candidates - Review application connection settings for the Cosmos DB SDK preferred regions list; regions that no client lists are serving only as replication or failover targets - Confirm with owners whether each extra region is required by a documented recovery or latency objective - Estimate the saving as the account's provisioned RU/s and stored GB multiplied by the number of regions that could be removed ## How to fix 5 ways to remove the waste. - Remove read regions with no traffic and no recovery requirement from Replicate data globally in the portal, or by updating the account's locations with the CLI, PowerShell or templates - Keep development, test and staging accounts single-region and without multi-region writes unless a test specifically needs them - Disable multi-region writes where single-region writes plus a read region meet availability needs, and review client consistency and failover settings first - Where a secondary region must remain only for disaster recovery, use autoscale with dynamic scaling so an idle secondary region scales down independently instead of matching the primary - Document the reason for each region in account tags so replication settings are reviewed when requirements change ## Documentation Vendor references for pricing and configuration. - [Optimize Cost for Multi-Region Deployments - Azure Cosmos DB learn.microsoft.com](https://learn.microsoft.com/en-us/azure/cosmos-db/optimize-cost-regions) - [Manage by Using the Azure Portal - Azure Cosmos DB learn.microsoft.com](https://learn.microsoft.com/en-us/azure/cosmos-db/how-to-manage-database-account) - [Create Containers and Databases with Autoscale Throughput - Azure Cosmos DB learn.microsoft.com](https://learn.microsoft.com/en-us/azure/cosmos-db/provision-throughput-autoscale) - [Monitoring Data Reference - Azure Cosmos DB learn.microsoft.com](https://learn.microsoft.com/en-us/azure/cosmos-db/monitor-reference) - [Azure Cosmos DB pricing azure.microsoft.com](https://azure.microsoft.com/en-us/pricing/details/cosmos-db/autoscale-provisioned/) ## Related inefficiencies [Browse the library](https://www.pointfive.co/efficiency-hub) - Azure Cosmos DB CER-0142 ### [Infrequently Accessed Data Stored in Azure Cosmos DB](https://www.pointfive.co/efficiency-hub/inefficiencies/infrequently-accessed-data-stored-in-azure-cosmos-db) Azure Cosmos DB is optimized for low-latency, globally distributed workloads - not long-term storage of infrequently accessed data. Yet in many environments, cold data such as logs, telemetry, or historical records is retained in Cosmos DB... Databases - Azure Cosmos DB CER-0438 ### [Idle Cosmos DB Containers with Provisioned Throughput](https://www.pointfive.co/efficiency-hub/inefficiencies/idle-cosmos-db-containers-with-provisioned-throughput) Containers and databases created for load tests, migrations, retired features, proofs of concept or one-off data loads often keep their provisioned throughput long after traffic stops. Provisioned RU/s is reserved capacity: it is billed... Databases - Azure Cosmos DB CER-0439 ### [Mismatched Throughput Mode on Cosmos DB Containers](https://www.pointfive.co/efficiency-hub/inefficiencies/mismatched-throughput-mode-on-cosmos-db-containers) Cosmos DB provisioned throughput comes in two modes. Standard (manual) throughput bills the RU/s you set every hour regardless of use. Autoscale lets the system scale between 10% and 100% of a maximum (Tmax) and bills the highest RU/s... Databases --- Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.