ONYX
BUSINESS MANAGEMENT
Welcome,
We’re Glad
you’re here.
Let’s take your
business to the
next level!
Precision. Innovation. Growth.
At Onyx, we provide expert financial management and innovative strategies that drive your business forward, helping you navigate challenges and seize opportunities for sustainable growth.
The Funds
Fundamentals
& Other Insights
2026 Tax Dates
MAR 16, 2026
FILE TAX RETURN
APR 15, 2026
FILE TAX RETURN
SEPT 15, 2026
EXTENSION DEADLINE
OCT 15, 2026
EXTENSION DEADLINE
FOR: S CORPORATIONS
File Form 1120-S for the calendar year and pay any tax due. Provide each shareholder with Schedule K-1. To request an automatic 6-month extension, file Form 7004 and submit any required estimated tax. To elect S Corporation status for 2026, file Form 2553.
FOR: PARTNERSHIPS
File Form 1065 for the calendar year and provide each partner with Schedule K-1 or K-3. For entities with foreign partners, file Forms 8804 and 8805. To request an automatic 6-month extension, file Form 7004.
FOR: INDIVIDUALS
File Form 1040 or 1040-SR and pay any tax due. To request an automatic 6-month extension, file Form 4868 and submit any required estimated tax. Pay the first installment of your 2026 estimated tax using Form 1040-ES.
FOR: PARTNERSHIPS
File Form 8813 quarterly payment voucher and pay any tax due.
FOR: CORPORATIONS
File Form 1120 for the calendar year and pay any tax due. To request an automatic 6-month extension, file Form 7004 and submit any required estimated tax.
FOR: INDIVIDUALS & CALENDAR YEAR-END ENTITIES
File Form 3520. To request an automatic 6-month extension, file Form 4868 (individuals) or Form 7004 (entities).
FOR: TAX-EXEMPT ORGANIZATIONS
Deposit estimated tax for the first quarter on unrelated business taxable income. Use Form 990-W to determine the required estimated tax payments.
FOR: HOUSEHOLD EMPLOYERS
File Schedule H with Form 1040 if you paid $2,800 or more to a household employee.
FOR: NON-RESIDENT ALIEN INDIVIDUALS
If you received wages subject to U.S. income tax withholding, file Form 1040-NR. To request an automatic 6-month extension, file Form 4868.
FOR: S CORPORATIONS & PARTNERSHIPS
If you are an S corporation or partnership that filed for an extension, your tax return is now due.
FOR: INDIVIDUALS, SOLE PROPRIETORSHIPS, & C CORPORATIONS
If you are an individual, sole proprietorship, or C corporation that filed for an extension, your tax return is now due.
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We specialize in expert bookkeeping services for businesses of all sizes. With precision and personalized attention, we keep your financial records accurate and up-to-date, allowing you to focus on the growth of your business.
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