Suno's default mix sits fairly narrow — width is something you add, not something you get. Two paths: prompt for it, or build it in the DAW.
1. Prompt for width: wide stereo mix, spacious, instruments spread across the stereo field in Style. Also doubled guitars panned left and right — specific width instructions beat general ones.
2. The stems width trick (biggest win): Get Stems, then in your DAW: pan drums slightly left/right per piece, push 'other' (keys/guitars) wide, keep bass and lead vocal center. Fifteen minutes of panning = a commercial-width mix.
3. Double-tracking: duplicate the 'other' stem, pan one copy hard left and the other hard right, delay one by 10-20ms. Instant width — this is the oldest studio trick there is.
4. Reverb for width: a short stereo reverb on backing elements (not the lead vocal) pushes them to the sides and opens the middle.
5. Keep bass and kick CENTER. Width is for the edges — low end in mono keeps the track punchy on every speaker, including phones.
Good luck! Hank founder of SonorixPG