Bookkeeping basics: what you need to track

Most small business owners know they're supposed to keep records. Fewer know specifically what records, how to organize them, or how long they need to hold on to them. The result is a lot of scrambling at tax time — hunting for receipts, reconstructing transactions, and hoping nothing's missing.

Good bookkeeping isn't complicated, but it is specific. Here's what you really need to track and why each piece matters.

Income

Every dollar that comes into the business needs to be recorded — invoices paid, cash receipts, payment platform deposits, refunds received, and any other revenue source. The goal is a complete, accurate picture of what the business earned, by category if you have multiple revenue streams.

Don't rely on your bank statement alone. Bank deposits can include non-income items (loans, owner contributions, reimbursements), and income can sometimes be received without hitting the main account. Your books need to capture revenue at the transaction level, not just at the deposit level.

For businesses that issue invoices, you also need to track accounts receivable — what's been billed but not yet collected. Outstanding receivables aren't income until they're received (under cash-basis accounting, which most small businesses use), but you still need to know what's owed to you.

Expenses

Business expenses need to be recorded individually, not just as lump sums, and they need to be categorized. The IRS requires that deductions be documented — a bank statement showing a charge to "Amazon" is not documentation that the purchase was a deductible business expense. You need the receipt or invoice that shows what was bought and that it was for business use.

Common expense categories to track: advertising and marketing, contract labor (1099 contractors), insurance, meals (business-purpose, 50% deductible), office supplies, professional services (accounting, legal, consulting), rent, subscriptions and software, telephone and internet, travel, and vehicle expenses.

The category matters because different expenses have different rules — some are fully deductible, some are partially deductible, some have dollar limits, and some require additional documentation. Recording everything as a generic "expense" makes it harder to catch deductions you're entitled to and harder to defend them if you're ever audited.

Owner draws, distributions, and wages to yourself

How money moves between you and the business needs to be tracked carefully — both what you take out and what you put in. The right treatment depends on your entity type. A sole proprietor records draws. An S corp owner records wages and distributions. A partner records guaranteed payments and draws. Each has different tax implications, and mixing them up creates problems.

Keep a clear record of every transfer between the business account and your personal account, labeled with what it is. "Owner draw" and "loan repayment" are not the same thing. "Capital contribution" and "revenue" are not the same thing. The label matters for your books and for your taxes.

Separate bank accounts — this isn't optional

Everything above depends on one thing being true first: your business and personal finances are in completely separate accounts. If they're not, your bookkeeping is broken at the foundation.

Commingled accounts create two problems. The first is practical: it's nearly impossible to accurately track business income and expenses when personal transactions are mixed in. The second is legal: courts and the IRS can look at commingled accounts as evidence that your business isn't truly a separate entity — which can cost you your liability protection and create unexpected tax problems.

Separate accounts, and route every business transaction through the business account. If you occasionally pay a business expense out of pocket, record it as a reimbursement to yourself.

Fixed assets and depreciation

Equipment, vehicles, computers, furniture, and other items you buy for the business and use over multiple years are called fixed assets, and they're tracked differently from regular expenses. Instead of deducting the full cost in the year you buy them, you typically depreciate them — spreading the deduction over their useful life.

There are exceptions: Section 179 expensing and bonus depreciation rules allow you to deduct some or all of the cost in the year of purchase, depending on the asset type and the year. But you still need records of what you bought, when you bought it, what you paid, and how it's being used in the business.

Keep purchase receipts for every significant asset you buy and a log of when each asset was placed in service. You'll need this information both for your tax return and for calculating gain or loss if you ever sell the asset.

Vehicle and mileage records

If you use a vehicle for business, you have two options for the deduction: actual expenses (gas, insurance, repairs, depreciation — all tracked and prorated by business use) or the standard mileage rate (a per-mile deduction, 67 cents per mile for 2024). Either way, you need a mileage log.

A mileage log needs to show: the date of each trip, the business purpose, the starting and ending location, and the number of miles driven. A vague entry like "client meeting, 45 miles" is better than nothing but may not hold up under scrutiny. The IRS is specific about what adequate records look like for vehicle deductions.

If you use your personal vehicle for business, be careful not to deduct commuting miles — travel between your home and your regular place of business isn't deductible. Business trips from your office to a client site are.

Payroll records

If you have employees (including yourself, if you're an S corp or C corp owner-employee), payroll records need to be tracked separately and with care. This includes wages paid, payroll taxes withheld, employer tax contributions, and payroll tax deposits. Payroll compliance has its own set of rules and deadlines, and errors can result in penalties.

Payroll tax records are subject to a four-year retention requirement (from the later of the due date of the tax or the date it was paid), which is longer than the general three-year period that applies to most other business records.

How long to keep records

The general rule is three years from the date you filed the return. The IRS normally has three years from the filing date to audit a return and assess additional tax. But there are exceptions that extend this window:

Six years if you underreported income by more than 25%. Seven years if you claimed a loss from worthless securities. No limit if you filed a fraudulent return or didn't file at all.

For employment tax records specifically, hold on to them for at least four years. For asset records — purchase receipts, depreciation schedules — keep them for as long as you own the asset plus the applicable statute of limitations period (so at minimum, three years after you sell or dispose of it). For contracts and legal documents, keep them for as long as they're relevant plus a few years beyond.

When in doubt, hold on to it. Storage is cheap; reconstructing records isn't.

A basic system that works

You don't need a complicated system — you need a consistent one. The essentials are a separate business bank account and credit card, bookkeeping software (QuickBooks, Wave, FreshBooks, and Xero are the most common options for small businesses), a way to capture receipts (a scanning app or a dedicated folder — physical or digital), and a mileage tracking app if you use a vehicle for business.

The frequency matters too. Bookkeeping done weekly or monthly is manageable. Bookkeeping done once a year at tax time, from twelve months of unorganized statements, is expensive — both in accountant time and in deductions you'll miss.

Want a one-page reference you can keep?

The Bookkeeping Basics checklist in the Prism resource library summarizes what to track, how to organize it, and what to keep — in a format you can print or save for reference.

Not sure if your books are in order?

A Vibe Check is a good place to start. We look at where you are and what needs attention — no judgment, just a clear picture of what to fix. Schedule yours here.

Keep reading

Bookkeeping is the foundation — these posts build on it:

• How to pay yourself from your business — How money moves between you and the business, and how to record it correctly by entity type.
• What your business structure means for your taxes — How your entity type determines what you file and how your income is taxed.
• Hiring your first employee: what you need to do — EIN, I-9, payroll setup, employer taxes, new hire reporting — here's everything you need to have in place before and after your first employee starts work.

This post is for general informational purposes and doesn't constitute tax or legal advice. Record retention requirements and bookkeeping rules can vary by situation — talk to a tax professional if you're unsure what applies to your business.