Estimated taxes for business owners: how quarterly payments work

When you work for someone else, taxes are withheld from every paycheck. When you own a business or work for yourself, no one does that for you. The U.S. tax system is pay-as-you-go, so the IRS expects you to pay tax throughout the year — generally through quarterly estimated payments.

Who generally needs to pay estimated taxes

You may need to make estimated payments if you have income that isn’t subject to withholding, such as:

• Self-employment or sole proprietorship income
• Income passed through from an S corporation, partnership, or multi-member LLC
• Rental income
• Significant interest, dividends, or capital gains

Individuals generally must make estimated payments if they expect to owe at least $1,000 in federal tax for the year after subtracting withholding and refundable credits. Many states, including Michigan, have their own estimated payment requirements.

When payments are due

For individuals on a calendar year, federal estimated payments are generally due:

• April 15 — for income earned January through March
• June 15 — for April and May
• September 15 — for June through August
• January 15 of the following year — for September through December

When a due date falls on a weekend or legal holiday, it moves to the next business day. Notice that the “quarters” aren’t equal — the second period is only two months long.

Safe harbor: how to avoid underpayment penalties

If you don’t pay enough during the year, you may owe an underpayment penalty even if you pay the full balance by April. The safe harbor rules give you a way to avoid that penalty. In general, you won’t owe the penalty if your withholding and timely estimated payments total at least the smaller of:

• 90% of the current year’s tax, or
• 100% of the prior year’s tax — or 110% if your prior-year adjusted gross income was more than $150,000 ($75,000 if married filing separately).

The prior-year method is popular because it’s predictable: you know the number in advance. But meeting the safe harbor only avoids the penalty. If this year’s income is much higher, you’ll still owe the difference when you file — which is where surprises come from.

Why business owners get caught off guard

• Growth. A strong year means last year’s numbers understate this year’s tax.
• Uneven income. Seasonal or project-based businesses may earn most of their profit in one part of the year.
• Pass-through income. S corporation and partnership profits are taxed to the owners whether or not the cash is distributed.
• Spending the tax money. Without a separate reserve, cash intended for taxes often gets used for operations.

A better approach

1. Keep books current. You can’t estimate what you owe without knowing what you’ve earned.
2. Project the year, not just the quarter. Revisit the estimate as results come in, especially before the September and January payments.
3. Set money aside as you earn it. A separate account for tax reserves turns estimated payments into a transfer instead of a scramble.
4. Coordinate with owner payroll. S corporation owners on payroll can use withholding as part of the plan.

Estimated taxes are one of the clearest examples of why tax planning works best as a year-round conversation.

This article is general information, not tax advice for your situation. Thresholds and rules can change; confirm current requirements with your CPA.