Common Digambar Jain surnames often include:

• Jain
• Sethi / Sheth
• Bhandari
• Kothari
• Mehta
• Lodha
• Khanna
• Patni
• Gadiya
• Pamnani
• Nemani
• Doshi
• Lunia
• Borad
• Sanganeria
• Kataria
• Hiralal / related family names in some regions
• Porwal
• Golalare
• Shrimal
• Maheshwari
• Oswal
• Agarwal

These surnames can vary a lot by region, tradition, and family history. In many Digambar Jain families, the surname may also reflect the original gotra, caste-group, or ancestral profession.

If you want, I can also give:

• region-wise Digambar Jain surnames
• common Digambar Jain gotras
• difference between Digambar and Shwetambar Jain surnames