License

The NServiceBus code base is permissively licensed to you, and for you.
You can use this code perpetually, worldwide, at no-charge, royalty-free.

The full license information to the source code is here.

The binary distributions of NServiceBus are available in two ways:

Free: This version includes all the transactional messaging functionality, retry logic, poison message handling with administrative return to source queue, windows service hosting and installation, as well as message handling unit testing.

Similar to Rails servers, the free version will be single threaded - capable of processing about 30 messages/s, or 2.5 million messages a day. Many processes can be deployed to the same box for even higher throughput, although with a slightly higher adminstrative overhead.

What is not included in this version is all the external production processes supporting scaling out to many-machine clusters, durable timeout management for long-running processes, and cross-site geographic message distribution.

Licensed: For companies requiring the greater performance and lower administration of multi-threaded message processing, commercial licenses and support are offered. Able to process about 1000 messages/s, or over 80 million messages a day - a single process is enterprise-ready for the most strenuous mission critical applications.

Available in bundles with BPM, grid, multi-site capabilities as well as support, there's a value/price point for every environment. See available licensing.