AWS Lambda increases maximum payload size from 256 KB to 1 MB for asynchronous invocations

AWS Lambda increases asynchronous invocations maximum payload size from 256 KB to 1 MB, allowing customers to ingest richer, complex payloads for their event-driven workloads without the need to split, compress, or externalize data. Customers invoke their Lambda functions asynchronously using either Lambda API directly, or by receiving push-based events from various AWS services like Amazon S3, Amazon CloudWatch, Amazon SNS, Amazon EventBridge, AWS Step Functions.

Modern cloud applications increasingly rely on AWS Lambda’s asynchronous invocations and its integration with various AWS serverless services to build scalable, event-driven architectures. These applications often need to process rich contextual data, including large-language model prompts, telemetry signals, and complex JSON structures for machine learning outputs. With increase in maximum payload size to 1MB for asynchronous invocations, developers can streamline their architectures by including comprehensive data, from detailed user profiles to complete transaction histories, in a single event, eliminating the need for complex data chunking or external storage solutions.

This feature is generally available in all AWS Commercial and AWS GovCloud (US) Regions. Customers can start sending asynchronous invocation payloads up to 1 MB using Lambda’s invoke API. Customers are charged for 1 request per each asynchronous invocation for first 256 KB. Individual payload size beyond 256 KB is charged 1 additional request for each 64 KB of chunk up to 1 MB. To learn more, read Lambda asynchronous invocation documentation and AWS Lambda pricing.