Posted On: Dec 15, 2020

Today, we are announcing the first FreeRTOS Long Term Support (LTS) release. With this release, developers can rely on a FreeRTOS version that provides feature stability, and security patches and critical bug fixes for two years. This makes it easier to identify and include only recommended changes to the FreeRTOS kernel and libraries, without adding the risk of introducing updates that could break an existing application.

The first FreeRTOS LTS release is FreeRTOS 202012.00 LTS. It includes the FreeRTOS kernel and IoT libraries — FreeRTOS+TCP, coreMQTT, coreHTTP, corePKCS11, coreJSON, AWS IoT Device Shadow. These libraries will be maintained at least until December 31, 2022.

The FreeRTOS LTS libraries have also been refactored to improve design flexibility, security, and code quality. First, LTS libraries are designed to be standalone — they have no dependencies on any additional libraries other than the standard C library. In addition, each LTS library now comes in its own GitHub repository, which makes it easier for developers to integrate and update libraries in their FreeRTOS projects. Second, LTS libraries have been validated for memory safety with the C Bounded Model Checker (CBMC) automated reasoning tool to mitigate code security issues such as buffer overflow. Lastly, they have undergone code quality checks including MISRA-C compliance and Coverity static analysis to ensure code safety, portability, and reliability in embedded systems (see LTS Code Quality Checklist).  

To get started, download the FreeRTOS 202012.00 LTS source code on For more information, please visit

See our blog post to learn more.