Frequently Asked Questions

PlainBizBench covers 1,000+ NAICS industry codes at the 2-, 3-, 4-, and 6-digit level, combining IRS Statistics of Income and Census Bureau County Business Patterns data.

Two sources: the IRS Statistics of Income program (aggregated business tax return data organized by NAICS code) and the Census Bureau County Business Patterns (employment, payroll, and establishment counts). Both are authoritative government datasets available to the public.

Profit margins are calculated as net income divided by total receipts for each NAICS code, using IRS Statistics of Income data. These are tax-reported figures from business tax returns, aggregated across all filers in each industry.

The North American Industry Classification System (NAICS) is the standard used by U.S. federal agencies to classify businesses by industry. NAICS codes range from 2-digit (broad sector, like 'Manufacturing') to 6-digit (specific sub-industry, like 'Dog and Cat Food Manufacturing').

The IRS suppresses data for NAICS codes with very few filers to protect taxpayer privacy. If an industry has fewer than a certain number of tax returns, the financial figures aren't published. This is an IRS policy, not a PlainBizBench limitation.

Census Bureau County Business Patterns data is typically 12–18 months behind the current year. IRS Statistics of Income data lags 2–3 years. We update our database when new data from either source is published.

PlainBizBench data is useful as a starting point for understanding industry benchmarks, but remember that averages reflect the full distribution of businesses in each NAICS code. A small startup will likely have very different margins than the industry average, which includes large established players. Always work with a qualified accountant for your specific situation.