There is no exact, universally recorded number of Jain families using the Soni surname.

In Jain communities, Soni is commonly found among many families, especially in Shwetambar and Oswal/Vaishya Jain traditions, but the count varies by region, lineage, and community records.

So, the correct answer is: many Jain families use the Soni surname, but no precise total is available.