Federal income tax rates for C corporations have been reduced to a flat 21%, starting in 2018 under the Tax Cuts and Jobs Act (TCJA). But what about pass-through businesses?

Congress devised a special tax break for pass-through businesses to help achieve parity between the reduced corporate income tax rate and the tax rates for business income that pass through to owners of sole proprietorships, partnerships, S corporations and limited liability companies (LLCs), which are treated as sole proprietorships or partnerships for tax purposes.

But not every pass-through entity is eligible for the break — and it isn’t always 20%. Here’s an overview of how much this deduction can amount to and which types of income count as qualified business income (QBI) under the new tax law.

How Much Is the Deduction?

Under prior law, net taxable income from pass-through business entities was simply passed through to owners and taxed at the owners’ level at the standard rates.

For tax years beginning after December 31, 2017, the TCJA establishes a new deduction based on a non-corporate owner’s QBI. This break is available to individuals, estates and trusts. The deduction generally equals 20% of QBI, subject to restrictions that can apply at higher income levels and another restriction based on taxable income.

A non-corporate owner’s deduction generally equals:

1. 20% of QBI from a partnership (including an LLC treated as a partnership for tax purposes), S corporation, or sole proprietorship (including a single-member LLC that is treated as a sole proprietorship for tax purposes), plus,

2. 20% of aggregate qualified dividends from REITs, cooperatives and qualified publicly traded partnerships (special rules apply to specified agricultural and horticultural cooperatives).

The QBI deduction isn’t subtracted in calculating the non-corporate owner’s adjusted gross income (AGI), but it reduces taxable income. In effect, it’s treated the same as an allowable itemized deduction. However, you don’t need to itemize to claim the QBI deduction.

Which Types of Income Count as QBI?

QBI is defined as the non-corporate owner’s share of items of taxable income, gain, deductions and loss from a qualified business. It includes interest income that’s properly allocable to a business, along with the aforementioned qualified dividends from REITs, cooperatives and publicly traded partnerships.

Investment-related items — such as capital gains and losses, dividends and interest income — don’t count as QBI. In addition, employee compensation and guaranteed payments from a partnership to a partner (including an LLC member who’s treated as a partner for tax purposes) don’t count as QBI.

Qualified items of income, gain, deductions and loss must be effectively connected with the conduct of a business within the United States or Puerto Rico.

Finally, QBI is calculated without considering any adjustments under the alternative minimum tax (AMT) rules.

Important: The QBI deduction and the applicable limitations are determined at the owner level. Each owner takes into account his or her share of qualified items of income, gain, deductions and loss from the pass-through entity and his or her share of W-2 wages paid by the entity.

Are There Any Restrictions?

In addition to being limited to 20% of your taxable income — calculated before the QBI deduction and before any net long-term capital gains (LTCGs) and qualified dividends that are eligible for preferential federal income tax rates — the QBI deduction is subject to two other limitations.

2. Service business limitation. Income from specified service businesses generally doesn’t count as QBI if the owner’s taxable income (not counting any potential QBI deduction) exceeds the applicable level. This limitation potentially affects income from such professions as:

Need Help?

Calculating the QBI deduction can be complicated. This article explains the basics, but additional factors may come into play, such as how business losses affect the QBI deduction calculation and how the deduction is calculated if you have income from several pass-through entities.

While the QBI deduction is beneficial, in some circumstances, it could make more sense to operate your business as a C corporation, which would be taxed at the flat 21% corporate income tax rate. Your PDR tax advisor can help you sort through the complexities and find the best tax-smart strategies for your specific personal and business circumstances.