NovaSeq X Plus

The largest of the Illumina sequencing instruments - enabling the generation of massive sequencing data amounts at competitive prices.

NGI now offers sequencing using Illumina’s NovaSeq X Plus system for dual flow cell sequencing, enabling refinement and scaling-up of short-read sequencing technology.

The NovaSeq X system uses 2-channel XLEAP-SBS chemistry with blue-green optics to encode data for the four base calls. A single-green signal represents “T”, single-blue signal represents “A”, dual color-green/blue signifies “C”, and black represents “G”.

This new system supports sequencing on three flow cell sizes:

Flow cellLanesAverage Yield (clusters/flowcell)Read length
1.5B21.6 billion100 cycles (e.g. 2x50bp)
200 cycles (e.g. 2x100bp)
300 cycles (e.g. 2x150bp)
10B88 billion – 10 billion*100 cycles (e.g. 2x50bp)
200 cycles (e.g. 2x100bp)
300 cycles (e.g. 2x150bp)
25B826 billion300 cycles (e.g. 2x150bp)
* These numbers represent an average yield based on our observations across projects. The yield for different libraries can vary depending on library type, concentration, fragment distribution, colour balance of indices, % PhiX spike-in, etc. Please consult with a Project Coordinator for guidance.

Index pooling recommendations:
Due to the new and updated chemistry on the NovaSeq X system, it is critical that the index combination is well-balanced so that the sequencing intensity signal is present in at least the green channel (preferably both color channels) for every cycle:
– Blue channel: A or C
– Green channel: C or T

If preparing your own sequencing libraries, always check the index pooling recommendations from the company providing the library preparation kit, and Illumina’s current version of the Index Adapters Pooling Guide for NovaSeq X. Indexing combinations may need to be revised prior to sequencing.

Last Updated: 13th March 2024

Please read our sample submission instructions before sending samples:

Sample Submission Guidelines
Method Status


We are routinely running this method. Please visit the Order Portal to place an order.