Is interest tax deductible?

Yes — when borrowed money is used for business. Interest on business loans, lines of credit, and business credit card balances is deductible as an ordinary business expense. The key principle is the tracing rule: what the money was used for determines whether the interest is deductible — not the type of loan or lender.

On this page: Short answer · Who this applies to · The tracing rule · Interest types · When it's deductible · When it's not deductible · Mixed-use debt · Schedule C · Example · Records · Specific lookups · FAQ

Short answer

Yes, for business-use borrowing. Interest is deductible when the borrowed funds are used to earn business income. Personal interest is generally not deductible. The deductibility follows the money — not the loan account.

Report business interest on Schedule C, Line 16b (Other Interest). Mortgage interest on a business property goes on Line 16a.

Recommended for small businesses

FreshBooks — Track loan interest and business expenses automatically

Categorize business loan interest, credit card charges, and financing costs throughout the year so your Schedule C Line 16 deductions are organized at tax time.

Who this typically applies to

Employees cannot deduct interest on personal loans used for work-related expenses under current tax rules.

The tracing rule: Why the use of funds matters

The IRS uses a tracing rule to determine whether interest is deductible. Under this rule, interest is classified based on how the borrowed funds were actually used — not based on the type of loan, the lender, or the account the money came from.

How the tracing rule works in practice

  • Business loan → business expenses: Interest is fully deductible as a business expense
  • Business loan → personal spending: Interest on that portion is personal — not deductible as a business expense
  • Personal credit card → business purchases: Interest on the business charges is deductible as a business expense
  • Personal credit card → mixed charges: Only the interest attributable to business charges is deductible
  • Home equity loan → business use: Interest may be deductible as business interest (not mortgage interest) if funds are traced to business use

The tracing rule means a personal credit card used exclusively for business purchases generates fully deductible interest. A business loan partially used for personal spending generates only partially deductible interest.

Interest types: Deductibility at a glance

Interest type Deductible? Where to report
Business loan interest Yes — fully deductible Schedule C, Line 16b
Business line of credit interest Yes — fully deductible Schedule C, Line 16b
Business credit card interest Yes — fully deductible Schedule C, Line 16b
Personal credit card — business charges only Business portion only Schedule C, Line 16b
Equipment financing interest Yes — business use portion Schedule C, Line 16b
Mortgage interest — business property Yes — fully deductible Schedule C, Line 16a
Mortgage interest — personal home Itemized deduction only Schedule A (not Schedule C)
Personal loan interest No Not deductible
Auto loan — personal vehicle No (personal use) Not deductible
Student loan interest Personal deduction only Form 1040, Schedule 1, Line 21

When interest is tax deductible

When interest is not deductible

Deducting interest on mixed-use debt

When borrowed funds are used for both business and personal purposes, only the business-use portion of the interest is deductible. The allocation follows the proportion of how the funds were actually spent.

Mixed-use debt allocation example

  • Total loan: $20,000
  • Used for business inventory: $15,000 (75%)
  • Used for personal expenses: $5,000 (25%)
  • Total interest paid in the year: $1,200
  • Deductible business interest: $1,200 × 75% = $900 → Schedule C, Line 16b
  • Non-deductible personal interest: $300

Keep bank statements or a spreadsheet showing how the borrowed funds were disbursed between business and personal use. This documentation supports your allocation if questioned.

Where does business interest go on Schedule C?

Business interest expenses go on Schedule C, Line 16 (Interest), which has two sub-lines:

Do not put personal credit card interest on Line 16b unless you have documented that the specific charges generating the interest were business expenses.

Example: Annual interest deductions for a freelance web developer

Example: Freelance developer carrying balances on business and personal cards

  • Dedicated business Visa card — all charges are business: interest paid in year = $340 → Line 16b ✓
  • Business line of credit for equipment purchase: interest paid = $780 → Line 16b ✓
  • Personal Mastercard — 70% of charges are business: total interest paid $200 × 70% = $140 → Line 16b ✓
  • Personal car loan (vehicle 60% business use, actual expense method): interest $600 × 60% = $360 — note: this goes on Line 9 (Car and Truck), not Line 16b
  • Personal student loan interest: $450 → not deductible on Schedule C (personal deduction on Schedule 1)
  • Total Schedule C business interest (Line 16b): $1,260

At a 22% effective tax rate, $1,260 in interest deductions saves approximately $277 in taxes. Vehicle loan interest is a separate calculation under actual vehicle expenses — it does not go on Line 16b.

What records to keep

Tax filing

TurboTax Self-Employed — Claim business interest deductions on Schedule C Line 16

TurboTax Self-Employed guides you through Schedule C Lines 16a and 16b, separates business interest from personal interest, and handles mixed-use debt allocation.

FAQ

Is business interest tax deductible?

Yes. Interest on money borrowed to fund business activities is generally tax deductible as an ordinary and necessary business expense. This includes interest on business loans, business lines of credit, and credit card interest on business purchases. Report on Schedule C, Line 16b. The deduction requires that you can trace the borrowed funds to business use.

Is personal interest tax deductible?

Generally no. Interest on personal loans, personal credit card balances, auto loans for personal vehicles, and consumer debt is not deductible as a business expense. Mortgage interest on a personal home may be deductible as an itemized deduction on Schedule A — but this is a personal deduction, not a business one.

Does it matter what the loan was used for?

Yes — the use of the borrowed funds determines deductibility, not the type of loan or the lender. This is called the tracing rule. If you borrow from a business loan account but use the funds for personal spending, that interest is not deductible. If you use a personal credit card for a business purchase, that interest is deductible for the business-use portion.

Is credit card interest tax deductible for business?

Yes, for the business-use portion. Interest on a dedicated business credit card is fully deductible. Interest on a personal credit card is deductible only for the portion of the balance attributable to business purchases. Keep statements showing which charges were business-related. Report on Schedule C, Line 16b.

Can I deduct interest on a mixed-use loan?

Yes, but only the business-use portion. If you borrowed $20,000 and used $15,000 for business and $5,000 personally, 75% of the interest is deductible as a business expense. Keep documentation showing how the borrowed funds were allocated between business and personal use.

Where does business interest go on Schedule C?

Business interest goes on Schedule C, Line 16 (Interest) — specifically Line 16b for most business interest including loans, lines of credit, and credit card interest. Mortgage interest on a business property goes on Line 16a. Personal mortgage interest goes on Schedule A, not Schedule C.

Looking for other deductible expenses? See the full Expense Deductibility Guide.

Last reviewed: April 14, 2026