What Can You Write Off? Understanding Business Expenses in QuickBooks
One of the most common questions business owners ask is, “Can I write this off?”
It’s an important question, but the answer isn’t simply about whether something was purchased for the business. Business owners need to understand why the expense was incurred, whether it is appropriate for the business, and what documentation supports it.
In Episode 43 of QuickBooks Mastery for Small Business Success, Erica Northrup and Lee Davis discuss what business owners need to know about deductions and how QuickBooks can help organize expenses before tax time.
Listen to Episode 43!
The goal isn’t to find every possible write-off.
The goal is to accurately identify legitimate business expenses and keep the documentation needed to support them.
What Has to Be True for Something to Be Deductible?
A business expense generally needs to be ordinary and necessary for the business.
In practical terms, the expense should be helpful and appropriate for the business.
This doesn’t mean that every expense has to be inexpensive. It means there should be a legitimate business reason for the purchase.
An expense that is unusual or excessive for the nature of your business may require additional scrutiny.
And there’s an important misconception to clear up:
A Deduction Doesn’t Make Something Free
When you deduct a legitimate business expense, you are reducing the amount of income subject to tax.
You are not getting the entire purchase price back.
For example, spending $1,000 on a deductible business expense doesn’t mean the government gives you $1,000 back. The deduction reduces your taxable income according to the applicable tax rules.
That’s why business owners should focus on making smart business purchases—not buying things simply because they might be deductible.
Ask Four Questions About Every Expense
When you’re trying to determine whether a purchase is a legitimate business expense, start with four questions:
1. What Did We Buy?
Be specific.
Don’t simply record something as “miscellaneous.”
Knowing exactly what you purchased makes it easier to determine how it should be categorized and whether it is a business expense.
2. Why Did We Buy It?
What was the business purpose?
Why was the purchase necessary or helpful to the business?
The purpose behind the expense matters.
3. What Part of This Is Personal?
Some purchases may have both business and personal components.
Identify the personal portion rather than automatically treating the entire transaction as a business expense.
Mixed transactions should be split appropriately.
4. What Documentation Do I Have?
What supports the purchase?
That might include:
- A receipt
- A bill
- An invoice
- A mileage record
- A business-purpose memo
- Other supporting documentation
Good documentation helps tell the story of the transaction.
Your Chart of Accounts Matters at Tax Time
Your Chart of Accounts is more than a list of categories inside QuickBooks.
It helps organize your business income and expenses and gives you a clearer picture of what happened during the year.
When your expenses are categorized correctly, you can review your Profit and Loss before tax time and see where your money actually went.
Some of the expense categories business owners may need to review include:
- Wages and overtime
- Bank charges
- Advertising
- Dues and subscriptions
- Legal expenses
- Accounting and bookkeeping
- Repairs and maintenance
- Office expenses
- Rent or lease
- Utilities
- Travel
The better organized these categories are, the easier it becomes to review your financial information and work with your tax professional.
Meals and Entertainment
Meals and entertainment are areas where business owners need to be particularly careful.
Entertainment expenses generally aren’t deductible under current federal tax rules, while qualifying business meals are generally subject to a 50% deduction limitation.
Meals also shouldn’t be lavish or extravagant under the applicable tax rules.
More importantly, don’t rely on your memory months later to explain a meal.
When recording a business meal, make a habit of documenting:
- Who attended
- What was discussed
- The date
- The amount
- Whether entertainment was part of the transaction
The more information you record at the time of the expense, the easier it is to support the transaction later.
Don’t Forget Vehicle Mileage
Vehicle expenses can become complicated quickly, particularly when a vehicle is used for both business and personal purposes.
One of the most important habits is to track your mileage.
Don’t wait until tax time and try to reconstruct an entire year’s driving from memory.
Keep your mileage records current so you can distinguish business use from personal use and provide the documentation needed to support the deduction.
Equipment and Fixed Assets
Not every large purchase should immediately be treated as an expense.
Equipment and other long-term purchases may need to be recorded as fixed assets and depreciated over time, depending on the applicable tax and accounting rules.
A useful concept discussed in the episode is the $2,500 safe harbor threshold. Businesses that elect the applicable safe-harbor treatment may generally expense certain qualifying items below that threshold rather than capitalizing them.
However, the $2,500 figure isn’t a universal rule that automatically determines how every purchase should be recorded.
The key question is whether the purchase provides value beyond the current year and how it should be treated under the applicable tax rules.
When you’re unsure, flag the purchase and discuss it with your accountant.
Loans: Don’t Expense the Entire Payment
Loan payments are another common area of confusion.
A loan payment generally contains two different components:
- Principal
- Interest
Interest is an expense.
Principal, however, reduces the amount you owe on the loan. It isn’t simply another business expense.
If you record the entire loan payment as an expense, you can distort your Profit and Loss and your Balance Sheet.
Your bookkeeping should separate these components so your financial statements accurately reflect what happened.
Make Documentation Part of the Process
One of the easiest ways to make tax preparation less stressful is to document expenses when you enter them.
Don’t wait until the end of the year.
When you enter a bill, attach the documentation right away.
At the same time, add a memo explaining the business purpose when appropriate.
If a transaction includes both business and personal expenses, split it when you record it.
These small habits can make a significant difference when you eventually need to review your books.
Do a Quick Expense Review Today
You don’t have to wait until tax season to start reviewing your deductions.
Open QuickBooks and take a look at your numbers now.
1. Run a Year-to-Date Profit and Loss
Run your Profit and Loss from January 1 through the current date.
Then compare it with the same period from last year.
Look for significant changes.
2. Review Your Major Expense Groups
Scan categories such as:
- Advertising
- Automobiles
- Meals
- Insurance
- Fees
- Repairs
- Utilities
- Travel
- Rent
- Supplies
- Subscriptions
- Licenses
- Depreciation
- Interest
You’re looking for expenses that are unusually high, unusually low, or significantly different from the prior year.
3. Open the Details Behind the Five Largest or Most Unusual Expenses
Don’t stop at the total on the Profit and Loss.
Open the transactions behind your five largest or most unusual expenses.
Ask:
What was this? Why did we purchase it? Is it categorized correctly? Do we have documentation?
4. Review Uncategorized and “Ask My Accountant” Accounts
Look for transactions that haven’t been properly categorized.
These accounts can contain important information that needs to be resolved before your financial statements are considered reliable.
Don’t allow transactions to sit there indefinitely.
5. Find Equipment and Vehicle Purchases
Review equipment and vehicle purchases.
Confirm that supporting documentation is attached and flag anything that may need to be treated as a fixed asset.
6. Review Loan Payments
Find your loan payments and confirm that principal and interest are being separated appropriately.
If the entire payment is being recorded as an expense, it’s worth investigating.
7. Check Three Meals, Travel, or Vehicle Expenses
Choose three transactions from meals, travel, or vehicle expenses.
Check whether each one has the appropriate documentation and business-purpose information.
If those three transactions aren’t well documented, that’s a good indication that you may need to improve your process for the rest of the year.
Good Bookkeeping Makes Tax Time Easier
Understanding deductions isn’t just about finding expenses to write off.
It’s about having accurate books that tell the story of your business.
When your Chart of Accounts is organized, your expenses are categorized correctly, documentation is attached, mixed transactions are separated, and unusual purchases are identified, you and your accountant have much better information to work with.
QuickBooks can help you organize that information, but it still requires good habits.
Enter the expense correctly. Document it immediately. Categorize it appropriately. Ask questions when something doesn’t make sense.
The Bottom Line
A tax deduction is a business expense that reduces taxable income—it isn’t free money.
Before treating an expense as deductible, ask four questions:
What did we buy? Why did we buy it? What part is personal? What documentation do we have?
Then use QuickBooks to organize the information and review your financial statements regularly.
The goal isn’t simply to maximize write-offs.
The goal is to have accurate, well-documented business expenses that you can confidently support.
Good bookkeeping throughout the year makes that process much easier—and can help you and your tax professional understand the complete financial story of your business.
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