---
title: "Expense tracking"
description: "Expense tracking means recording each business expense with proof as it happens. What records the IRS expects and how long to keep them."
canonical: https://engine.com/glossary/expense-tracking
updated: 2026-11-02
author: "Engine Editorial"
---

# Expense tracking

Expense tracking is recording each business expense as it happens, with a receipt or other document that proves it, so the books show where money went.

Also called: tracking business expenses

Updated November 2, 2026 by Engine Editorial

## What is expense tracking?

Expense tracking is keeping a running record of business spending, backed by receipts. This cheat sheet covers how to think about it and where it breaks down. The detail is further down.

### How to think about it

- **Every expense needs proof.** The IRS says supporting documents should show the payee, the amount, proof of payment, the date and what was bought.
- **Record it near the time.** A record made at or near the time of the expense carries more weight than one prepared later from memory.
- **Keep business money separate.** A business bank account keeps company and personal spending apart, and for most small businesses it is the main source for the books.
- **Software counts.** Electronic records are fine, as long as they meet the same rules as paper books.

### Where tracking breaks down

- **Manual entry.** Logging expenses by hand leads to missed or duplicated transactions, keying errors and wrong totals.
- **Time lags.** The longer it takes to record and review expenses, the less accurate the books are.
- **Estimates.** You can't deduct amounts you approximate or estimate.
- **A statement alone.** A bank or card statement may not show what was bought, so keep the receipt as well.

## How it works on Engine

For travel, [Engine reporting](https://engine.com/features/travel-reporting-analytics) uses booking and billing data captured in the platform instead of receipts, statements and spreadsheets. Company fields like department, project, job code and cost center add the context finance needs for filtering and reconciliation. Choose those fields before bookings begin. Trips booked outside Engine aren't included automatically.

## Track travel spend without the spreadsheet

Engine reporting uses the booking and billing data captured in Engine, filterable by department, project, team or cost code. Free to use.

[Get started](https://engine.com/sign-up)

## Questions

### What records should a business keep for expenses?

The IRS lists canceled checks or other proof of payment, cash register tape receipts, account statements, credit card receipts and statements, and invoices. A combination may be needed to support every element of an expense.

### How long should you keep expense records?

Generally 3 years from the date you file the return that claims the deduction. Employment tax records should be kept for at least 4 years.

### Is a credit card statement enough to track an expense?

Not always. A statement may not itemize the purchase, and the IRS notes a combination of documents may be needed to support all elements of an expense.

### Can I track business expenses in a spreadsheet?

Yes. A small company with straightforward finances may find a spreadsheet enough, and the IRS treats a record kept on a computer as an adequate record.

## Go deeper

- [How to manage and track business expenses](https://engine.com/blog/how-to-manage-business-expenses)
- [Expense receipts and valid proof of purchase](https://engine.com/blog/expense-receipts)
- [Engine travel reporting](https://engine.com/features/travel-reporting-analytics)
- [Expense reconciliation](https://engine.com/glossary/expense-reconciliation)

## Sources

1. Internal Revenue Service, "What kind of records should I keep," https://www.irs.gov/businesses/small-businesses-self-employed/what-kind-of-records-should-i-keep, accessed November 2, 2026.
2. Internal Revenue Service, "Publication 463 (2025), Travel, Gift, and Car Expenses," https://www.irs.gov/publications/p463, accessed November 2, 2026.
3. Engine, "How to manage & track business expenses in 7 steps," https://engine.com/blog/how-to-manage-business-expenses, accessed November 2, 2026.
4. Engine, "Expense receipts: What are valid proofs of purchase?," https://engine.com/blog/expense-receipts, accessed November 2, 2026.
5. Engine, "Travel Reporting and Analytics," https://engine.com/features/travel-reporting-analytics, accessed November 2, 2026.