What is cash basis accounting?

Cash basis accounting is an accounting method that records revenue when cash is received and expenses when cash is paid, regardless of when services are delivered or obligations incurred. For professional service firms, the cash basis is simpler than accrual accounting. Still, it provides a less accurate picture of business activity and is not permitted for firms exceeding certain revenue thresholds. Most growing professional service firms eventually transition to accrual accounting for better financial visibility.

Key characteristics

• Records revenue when cash is received, expenses when cash is paid

• Simpler than accrual accounting, with less tracking required

• Does not match revenue to the period services delivered

• Not GAAP-compliant for larger or more complex businesses

• IRS limits cash basis for firms with over $29 million in revenue

• Provides poor visibility into actual business performance

Why it matters for professional service firms

Cash basis accounting appeals to small firms for its simplicity, but creates problems as businesses grow. A firm that bills $100K in December but collects in January shows December as slow and January as strong, when reality is the opposite. Cash basis makes financial performance difficult to assess and creates tax timing opportunities that may not serve long-term interests. Most professional service firms should transition to accrual accounting once they have consistent billing and seek greater visibility into performance.

Real-world example

Sarah's consulting firm used a cash basis through $800K revenue. December reported $45K in revenue (a weak month), while January reported $180K (a record month). Reality: December had $130K in billings collected in January. Cash basis masked true performance patterns. At $1.2M in revenue, Sarah transitioned to accrual accounting. Now, December showed $130K earned revenue regardless of collection timing. Monthly patterns became clear, enabling better decisions about capacity, seasonality, and pipeline needs. Tax planning also improved because income recognition aligned with actual work delivery rather than collection timing.