# Unnecessary costs from unused Lambda versions with SnapStart Canonical: https://www.pointfive.co/efficiency-hub/inefficiencies/unnecessary-costs-from-unused-lambda-versions-with-snapstart Many teams publish new Lambda versions frequently (e.g., through CI/CD pipelines) but do not clean up old ones. By: Jake McCracken Updated: 2026-09-28 [Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) # Unnecessary Costs from Unused Lambda Versions with SnapStart The short version Many teams publish new Lambda versions frequently (e.g., through CI/CD pipelines) but do not clean up old ones. [Jake McCracken](https://www.linkedin.com/in/jake-mccracken-144a92a4/) Cloud FinOps Senior Manager @ Wood Mackenzie AWS service [AWS Lambda](https://www.pointfive.co/efficiency-hub/cloud-services/aws-lambda) Category [Compute](https://www.pointfive.co/efficiency-hub/service-category/compute) Reference CER-0209 Type Outdated Version ## Explanation Why the waste happens and who it affects. When SnapStart is enabled on Python or .NET functions, each of these versions retains a cached snapshot, generating ongoing charges. Over time, accumulated unused versions can significantly increase spend without delivering any business value. This problem compounds in environments with high deployment velocity or many functions. ## Billing model The pricing dimensions that drive this cost. For Python and .NET managed runtimes, Lambda SnapStart charges a cache fee for every published function version with SnapStart enabled. The fee depends on allocated memory, has a 3-hour minimum, and keeps accruing while the version exists, even if it is no longer invoked. Each restore from a snapshot is also charged. On Java managed runtimes SnapStart has no additional cost, and Lambda deletes a Java version's snapshot after 14 days without an invocation. ## How to detect 4 checks to find it in your estate. - Review the number of published Lambda versions with SnapStart enabled on Python and .NET runtimes across accounts - Assess whether older versions are still being invoked or if they remain idle but cached - Correlate Lambda costs with the number of SnapStart-enabled versions retained in each environment - Check for environments with frequent deployments where unused versions may accumulate ## How to fix 4 ways to remove the waste. - Delete unused Lambda function versions with SnapStart enabled to eliminate unnecessary cache charges - Implement version lifecycle management practices in CI/CD pipelines to automatically clean up old versions - Retain only the most recent versions required for rollback or audit purposes - Monitor the number of SnapStart-enabled versions per function and enforce limits to prevent sprawl ## Documentation Vendor references for pricing and configuration. - [Improving startup performance with Lambda SnapStart docs.aws.amazon.com](https://docs.aws.amazon.com/lambda/latest/dg/snapstart.html) - [Activating and managing Lambda SnapStart docs.aws.amazon.com](https://docs.aws.amazon.com/lambda/latest/dg/snapstart-activate.html) - [AWS Lambda Pricing aws.amazon.com](https://aws.amazon.com/lambda/pricing/) ## Related inefficiencies [Browse the library](https://www.pointfive.co/efficiency-hub) - AWS Lambda CER-0296 ### [Inefficient Lambda Pricing Model for Steady High-Volume Workloads (Use Lambda Managed Instances)](https://www.pointfive.co/efficiency-hub/inefficiencies/inefficient-lambda-pricing-for-steady-high-volume-workloads-use-lambda-managed-instances) A function has steady, high-volume traffic (or predictable load) but continues running on default Lambda pricing, where costs scale with execution duration. Lambda Managed Instances runs Lambda on EC2 capacity managed by Lambda and... Compute - AWS Lambda CER-0290 ### [Unnecessary Lambda Provisioned Concurrency on Low-Utilization Functions](https://www.pointfive.co/efficiency-hub/inefficiencies/unnecessary-lambda-provisioned-concurrency-on-low-utilization-functions) Provisioned Concurrency is enabled for Lambda functions that do not require consistently low latency or steady traffic. In such cases, provisioned concurrency remains allocated and billed during idle periods, creating ongoing cost without... Compute - AWS Lambda CER-0204 ### [Inefficient SnapStart Configuration in Lambda](https://www.pointfive.co/efficiency-hub/inefficiencies/inefficient-snapstart-configuration-in-lambda) SnapStart reduces cold-start latency, but when configured inefficiently, it can increase costs. For Python and .NET functions, high-traffic workloads can trigger frequent snapshot restorations, multiplying costs. Slow initialization code... Compute --- Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.