MTS is a AVCHD container format developed by Sony and Panasonic for HD camcorder users. Now .MTS file format is widely used by more HD camcorder like Sony, JVC, Canon, etc for recording 1080i or 720p HD videos.

M2TS is container media format for multiplexing audio, video and other streams. .M2TS video files is based on the MPEG-2 transport stream container and commonly used by Blu-ray Disc and AVCHD camcorder.

1.The two are different extensions used for the same container format.
2.MTS is the extension used in legacy file systems while M2TS is used in more modern ones.
3.MTS usually means that the file comes from an AVCHD camcorder while M2TS is from proper Blu-ray.

Other Comparison: 3GP vs 3G2 / MP4 vs FLV / MKV vs MP4 / MP4 vs MP3 / 3GP vs MOV / 3GP vs FLV / M2TS vs MP4 / MP4 vs 3GP

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