What is an Underpayment penalty?

An underpayment penalty is an IRS-imposed interest charge assessed when taxpayers fail to pay sufficient federal income tax throughout the year through withholding, quarterly estimated tax payments, or a combination of both. The penalty is calculated separately for each quarterly period using the federal short-term rate plus 3 percentage points. Taxpayers can avoid penalties by meeting the safe harbor requirements of paying 100% of the prior year tax (110% for high earners) or 90% of the current year tax. Traditional 401k contributions reduce income subject to quarterly estimates.

Related Terms

What are Estimated tax payments?

What are Withholding allowances?

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Tax loss harvesting

Transform investment losses into strategic tax advantages and optimize your portfolio's performance with AI-driven precision.

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Child traditional IRA

Open a Traditional IRA for children with earned income. Contribute up to $7,000 annually with full deduction, giving them decades to grow tax-free.

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Employee achievement awards

Award your team for service milestones and safety achievements while maximizing allowable deductions up to $1,600 per employee.

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Health reimbursement

Set aside money on a pre-tax basis to pay for qualified medical expenses to maximize tax savings opportunities.

Mom helps daughter bake cookies, showing $2,000 tax savings with tax forms 1040 and 8812.

Child & dependent tax credits

Claim up to $2,000 per child & $500 per other dependent. Automatically maximize your child and dependent-related tax credits.

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Health savings account

Set aside money on a pre-tax basis to pay for qualified medical expenses to maximize tax savings opportunities.

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Sell your home

Transform your home sale into a tax-saving opportunity.

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Employee achievement

Skill up your team, scale down your business expenses.

Military Veteran hiring approved with tax credit forms and a 46% savings increase from last year.

Work opportunity tax credit

Unlock tax savings for empowering your community through hiring.

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Oil & gas deduction

Drill into tax savings. Maximize deductions for both tangible and intangible drilling costs.

A woman and child reviewing W-2 tax forms for family business, showing 46% tax savings.

Hiring kids

Reduce taxable income & self-employment tax by hiring your kids.

Home office

Deduct qualified expenses for using your home for business purposes.

Meal expenses

Business can typically deduct 50% of meals associated with doing business with some cases allowing up to 100% deduction.

Travel expenses

Businesses can deduct necessary travel expenses, like airfare and lodging, directly related to operations for tax savings.

Vehicle expenses

Vehicle tax deduction allows deduction of business vehicle expenses, using a per-mile rate or actual costs, from taxable income.

Late S election

A Late S Election lets a corporation request IRS S corp status post-deadline.

Late C election

A Late C Election is a request to the IRS for C corporation status after the deadline.

Depreciation

Put your fixed assets to work for you by utilizing depreciation to find and compare tax savings in minutes.

R&D tax credit

Fuel your venture's growth and innovation with the R&D tax credit. Not just for tech firms or big corporations.

Clean vehicle

Businesses and Individuals can receive a tax credit for purchasing new eco-friendly vehicles. Individuals may also qualify on used eco-friendly vehicles.

Residential clean energy

Taxpayers who invest in renewable energy improvements for their home or second home may qualify for a credit to lower their income tax.

Augusta rule

The Augusta Rule lets homeowners rent their property tax-free for up to 14 days a year without reporting the income.

Roth 401k

Roth 401(k) lets employees and individuals make after-tax retirement contributions, offering tax-free growth and withdrawals.

Traditional 401k

Traditional 401(k) plans offer pre-tax retirement savings for employees, with companies reducing taxable income via contributions.