Close this search box.

Table of Contents

Ordinary and Necessary Expense (O&NE)


The term “Ordinary and Necessary Expense (O&NE)” refers to expenses that are common, accepted in a particular trade, and appropriate for the operation of a business. In general, these expenses are tax-deductible and must meet the criteria set by the Internal Revenue Service (IRS). They can range from employee salaries, rent, supplies, to advertising costs and professional services.


The phonetic pronunciation for the phrase “Ordinary and Necessary Expense (O&NE)” would be:Ordinary – /ˈɔːrdəˌneri/and – /ænd/Necessary – /ˈnesəˌseri/Expense – /ɪkˈspens/O&NE – /oʊ ænd ɛn iː/

Key Takeaways

1. Relevance to Conducting Business: O&NE refers to expenses that are both ordinary and necessary for conducting business. Ordinary expenses are common and accepted in a particular trade or business, while necessary expenses are those that are appropriate and helpful in running a business.

2. Tax Deductibility: O&NE are often important for tax purposes, because these types of expenses generally qualify as tax-deductible for businesses. This means businesses can subtract these costs from their revenue to determine their taxable income, lowering their tax liability and helping them save money.

3. Documentation Requirement: Businesses need to keep accurate records of their O&NE to provide evidence for their tax deductions. Documentation can include receipts, invoices, or other written records that clearly show both the amount of the expense and the purpose for which it was incurred.


The term “Ordinary and Necessary Expense (O&NE)” is important in business/finance as it determines the tax-deductible expenses for conducting day-to-day business operations. These are expenditures that are customary and essential to run a business and are not lavish or extraneous. The ability to deduct these expenses reduces a company’s taxable income, thereby potentially decreasing its tax liabilities significantly. It’s crucial for businesses to correctly identify and track these expenses to ensure accurate tax returns and financial reports. Misunderstanding or misrepresenting what constitutes an ordinary and necessary expense can lead to potential tax penalties or audit issues. This concept therefore plays an essential role in budgeting, expense management, and strategic tax planning for businesses.


Ordinary and Necessary Expense (O&NE) is an essential business term that helps in understanding and categorizing costs within an organization. Its distinctive value lies in its purpose, specifically supporting tax deductions for businesses. Organizations spend on numerous things in their daily operations, and while not all costs can be considered for tax deductions, the ones falling under O&NE stand as a significant exception. They help businesses reduce their taxable income and consequently their tax liability, thus having a profound impact on a company’s net income and overall financial health.Guidelines for what can be qualified as an O&NE typically revolve around the expense being both “Ordinary” and “Necessary” , which are relative terms within specific business contexts. An “Ordinary” expense is one that is common and accepted in the respective industry of the taxpayer or the business. On the other hand, a “Necessary” expense is one that is helpful and appropriate for the business or trade. By classifying and tracking these expenses accurately, businesses can leverage the benefits of tax deductions, improving their fiscal efficiency, while ensuring their actions are consistent with legal and accounting principles.


1. Office Supplies: If you’re running a business, it’s ordinary and necessary to purchase office supplies like paper, pens, printer ink, etc. These are everyday items that are integral to the functioning of the office and the completion of day-to-day tasks. Therefore, according to IRS guidelines, they can be deducted as business expenses.2. Business Travel: This includes costs associated with traveling for business purposes such as transportation (flights, car rentals), lodging/accommodation, and meals. For instance, if you own a business and need to attend a conference or meet a client in another city, these costs are considered ordinary and necessary to running your business and can be deductible.3. Employee Salaries: Employee compensation is also a typical ordinary and necessary expense. It is routine for a business to require staff to operate and it is compulsory to pay them for their work. Thus, salaries and wages paid to employees are necessary to keep the business operational and are tax-deductible expenses.

Frequently Asked Questions(FAQ)

What is an Ordinary and Necessary Expense (O&NE)?

An Ordinary and Necessary Expense (O&NE) refers to costs that are common, accepted, helpful, and appropriate for a particular business, trade, or industry.

Can you give examples of Ordinary and Necessary Expenses?

Sure. Examples could include costs like rent, utilities, office supplies, and equipment. These are routinely incurred in the course of running a business and are considered necessary for its operation.

Are all business expenses classified as Ordinary and Necessary?

No, not all business expenses qualify as Ordinary and Necessary. Notably, extravagant or lavish expenses are typically excluded, even if they could potentially contribute to business operations.

How does the Internal Revenue Service (IRS) view Ordinary and Necessary Expenses?

As per IRS guidelines, Ordinary and Necessary business expenses are typically deductible. However, they must not be excessive and should be directly linked to conducting business.

How can I determine if an expense is Ordinary and Necessary?

Generally, if an expense is common and accepted in your trade or business, and if it is helpful and appropriate for your business, it can be deemed an Ordinary and Necessary Expense.

Can an O&NE be personal?

No, an O&NE must be directly linked to the business. Personal expenses are not accepted as O&NE, even if they indirectly affect business operations.

Who determines the validity of an Ordinary and Necessary Expense claim?

Typically, the business, an accountant, or a tax preparer will categorize an expense as Ordinary and Necessary. However, the IRS will have the final say and may audit expenses if they find them suspicious or not within the guidelines.

Is O&NE applicable to all types of businesses?

Yes, the concept is applicable to all types of businesses, be it small, medium or large. Even self-employed individuals can use the O&NE concept for their tax deductions. However, the specific expenses that qualify may vary depending on the industry, trade, or business type.

How often can I claim O&NE deductions?

You can typically claim O&NE deductions for each tax year, as long as the expenses reported were incurred in that specific year in the course of conducting business.

Can capital expenditure be classified as Ordinary and Necessary Expense?

No, capital expenditures, or CapEx, are usually not classified as O&NE. These are costs incurred to acquire or upgrade physical assets like property or equipment, which usually provide long-term benefits, and are not part of everyday operational costs.

Related Finance Terms

  • Tax Deduction
  • Business Expense
  • Internal Revenue Service (IRS)
  • Schedule C
  • Operating Costs

Sources for More Information

About Our Editorial Process

At Due, we are dedicated to providing simple money and retirement advice that can make a big impact in your life. Our team closely follows market shifts and deeply understands how to build REAL wealth. All of our articles undergo thorough editing and review by financial experts, ensuring you get reliable and credible money advice.

We partner with leading publications, such as Nasdaq, The Globe and Mail, Entrepreneur, and more, to provide insights on retirement, current markets, and more.

We also host a financial glossary of over 7000 money/investing terms to help you learn more about how to take control of your finances.

View our editorial process

About Our Journalists

Our journalists are not just trusted, certified financial advisers. They are experienced and leading influencers in the financial realm, trusted by millions to provide advice about money. We handpick the best of the best, so you get advice from real experts. Our goal is to educate and inform, NOT to be a ‘stock-picker’ or ‘market-caller.’ 

Why listen to what we have to say?

While Due does not know how to predict the market in the short-term, our team of experts DOES know how you can make smart financial decisions to plan for retirement in the long-term.

View our expert review board

About Due

Due makes it easier to retire on your terms. We give you a realistic view on exactly where you’re at financially so when you retire you know how much money you’ll get each month. Get started today.

Due Fact-Checking Standards and Processes

To ensure we’re putting out the highest content standards, we sought out the help of certified financial experts and accredited individuals to verify our advice. We also rely on them for the most up to date information and data to make sure our in-depth research has the facts right, for today… Not yesterday. Our financial expert review board allows our readers to not only trust the information they are reading but to act on it as well. Most of our authors are CFP (Certified Financial Planners) or CRPC (Chartered Retirement Planning Counselor) certified and all have college degrees. Learn more about annuities, retirement advice and take the correct steps towards financial freedom and knowing exactly where you stand today. Learn everything about our top-notch financial expert reviews below… Learn More