Small-Business Tax Rates Explained: A 2026 Guide

Small businesses in the United States face a patchwork of federal tax rates determined by their legal structure, with pass-through entities paying personal income tax rates that range from 10% to 37% and C corporations subject to a flat 21% levy, according to a NerdWallet analysis [1]. The Internal Revenue Service does not apply a single rate to all business income. Instead, it uses a progressive system where income is taxed in segments. Sherman Standberry, a certified public accountant and founder of My CPA Coach, described the mechanism: “The incremental tax system basically taxes your income in buckets” [1]. For a sole proprietor with $150,000 in taxable income after deductions, the first $12,400 is taxed at 10%, the next $38,000 at 12%, the following $55,300 at 22%, and the remaining $44,300 at 24%, resulting in a total federal income tax bill of $28,598 [1]. Business structure is the primary driver of tax liability. Pass-through entities, such as sole proprietorships, partnerships, and S corporations, report business income on the owner’s individual return, where marginal rates top out at 37% [1]. C corporations pay a flat 21% on their profits [1]. Beyond income tax, businesses that are not S or C corporations owe self-employment tax at 15.3% of income, while those with employees pay employment taxes equal to 13.65% of payroll [1]. The U.S. framework sits within a complex global landscape. Comparing tax rates across countries is difficult because tax laws are extremely complex and the burden falls differently on different groups, and the rates displayed are marginal and do not account for deductions, exemptions, or rebates [2]. In the United Kingdom, for instance, central government revenue comes primarily from income tax, National Insurance contributions, value added tax, and corporation tax, with total government revenue forecast at £1,139.1 billion for the 2023–24 fiscal year [4]. Recent federal legislation has reshaped the domestic tax environment. The One Big Beautiful Bill Act, signed into law on July 4, 2025, permanently extended the individual tax rates originally enacted in 2017, which were set to expire at the end of 2025 [5]. The law also raised the cap on the state and local tax deduction to $40,000 for taxpayers making less than $500,000, though that cap is scheduled to revert to $10,000 after five years [5]. The Congressional Budget Office estimates the law will increase the budget deficit by $2.8 trillion by 2034 [5]. CPAs interviewed by NerdWallet stressed that deductions are a key lever for reducing taxable income. Standberry noted that many business owners overlook expenses related to home offices, vehicles, and travel [1]. A CPA identified only as Saleh advised that deductions should tell a coherent story in case of an IRS audit, recommending that taxpayers create clear documentation, such as recording odometer readings with an oil change at the start and end of the year to substantiate a standard mileage deduction [1]. Saleh also cautioned that some LLCs and sole proprietorships attempt to reduce liability by electing S corporation status to eliminate the 15.3% self-employment tax, but often fail to follow the rules regarding reasonable compensation, which can trigger penalties [1]. Standberry emphasized the importance of timing in tax planning. “If you want to reduce your taxes, you need to do something before December 31,” he said [1]. He also distinguished between marginal and effective tax rates, explaining that while he focuses on the marginal rate to find savings, the effective rate—calculated by dividing the total tax bill by taxable income—shows what a business owner is actually forfeiting from their income and aids in budgeting for quarterly estimated payments [1].