I bought my wife a new phone for her self employed business but also uses it for personal. Is the cost of the physical phone deducible under De Minimis Expense Threshold?

[whit09]

I bought my wife a new iPhone for her business but she uses it for personal use as well. Quickbooks is telling me this is a business asset that falls under the safe harbor De Minimis Expense Threshold. If the phone was $800, is all $800 deductible as a business asset or only a portion because there is some personal use as well? All the questions I could find regarding this were questions about cell phone "costs" which most questions are referring to you month bill. I want to know about the actual physical phone cost, not the bill. 

[MarilynG]

If she uses the phone 80% for business (for instance) you can deduct 80% of the cost of the phone and 80% of the monthly bill as business expenses.

When you enter a business asset, TurboTax will ask the Cost and the Business Use %.

However, you are correct that you can deduct the new phone as a one-time Business Expense, rather than setting it up as a Business Asset.  

In this case, you would enter the business portion of the phone cost in the Business Expenses section (see screenshot).