Can I deduct a second phone line for business?

Yes — in general, you can deduct a second phone line for business if it is used for business and the expense is ordinary and necessary for that business.

For IRS purposes, the basic rule is:

• The cost of your first home telephone line is generally not deductible just because you use it for business.
• A second line used only for business is generally deductible as a business expense.
• If a line is used for both personal and business purposes, you can usually deduct only the business-use portion, and you should keep records to support the split.

What to keep in mind

• Service charges: Business-only line charges, taxes, and fees are typically deductible if properly documented.
• Mixed use: If you also use the line personally, only the business portion is generally deductible.
• Equipment/devices: A phone or handset bought for business may be deductible, depreciated, or potentially expensed depending on the facts and current tax rules, but this is not automatic for every purchase.

Documentation

Keep itemized bills, call or usage logs, and proof that the second line is used for business. Exact treatment can vary depending on whether it’s a home office, a mobile line, or a business entity expense, so it’s worth checking the current IRS guidance or a tax professional before filing.