Key Internal Revenue Code (IRC) Sections Explained

Understanding the specific legal sections governing business taxation prevents overpayment and shields your entity from audit liabilities.

IRC §199A - Qualified Business Income (QBI) Deduction

Allows eligible sole proprietorships, partnerships, and S-corporations to deduct up to 20% of their qualified business income. High-income thresholds trigger W-2 wage and Unadjusted Basis Immediately After Acquisition (UBIA) property limitations.

IRC §465 - At-Risk Limitations

Restricts pass-through business owners from deducting losses that exceed their personal financial risk in the activity. Debt financing must be correctly categorized as recourse, nonrecourse, or qualified nonrecourse to determine allowable loss deductions.

IRC §469 - Passive Activity Loss (PAL) Rules

Disallows taxpayers from using passive losses (e.g., rental real estate or non-materially participating business shares) to offset non-passive income like W-2 wages or active business income. Unused passive losses carry forward indefinitely until the asset is fully disposed of.

IRC §704(b) - Substantial Economic Effect

Requires partnership special allocations of income, gains, losses, and deductions to accurately reflect the economic arrangement of the partners. Partner capital accounts must be maintained under strict §704(b) accounting rules.

IRC §6698 - Failure to File Partnership Returns

Imposes severe late-filing penalties on partnerships that miss March 15 (or extended September 15) deadlines. The IRS assesses a penalty per partner, per month (up to 12 months), rapidly accumulating into thousands of dollars in automatic fines.

Federal Tax Deadline & Form Quick Reference (2026 Tax Year)

Note: An extension grants extra time to submit tax paperwork, but does not extend the time to pay taxes owed.

Form Type	Entity Description	Original Filing Due Date	Extension Form	Extended Final Due Date
Form 1065	Partnerships & Multi-Member LLCs	March 15, 2026	Form 7004	September 15, 2026
Form 1120S	S-Corporations	March 15, 2026	Form 7004	September 15, 2026
Form 1040	Individuals & Sole Proprietors	April 15, 2026	Form 4868	October 15, 2026
Form 1120	C-Corporations	April 15, 2026	Form 7004	October 15, 2026

Official IRS Record Retention Guidelines

How long should you keep tax returns, receipts, and supporting financial documents? Follow these statutory timelines:

• 3 Years (Standard Rule): Keep records for 3 years from the date you filed your original return or 2 years from the date you paid the tax, whichever is later. Covers standard receipts, 1099s, W-2s, and bank statements.
• 6 Years (Unreported Income): Keep records for 6 years if you fail to report income that you should have reported, and it amounts to more than 25% of the gross income shown on the return.
• 7 Years (Loss Claims): Keep records for 7 years if you file a claim for a loss from worthless securities or bad debt deduction.
• Indefinitely (Unfiled/Fraudulent Returns): Keep copies of all tax returns, W-2s, and corporate formation documents indefinitely. If a return was not filed or was fraudulent, the IRS statute of limitations never expires.
• Property & Asset Records: Keep asset records (real estate closing statements, stock buy/sell confirmations, depreciation schedules) until the statute of limitations expires for the tax year in which you sell or dispose of the asset.

IRS Audit Notices & Penalty Abatement Resolution

Received an IRS letter or facing late penalties? Here is what you need to know about IRS notices and penalty forgiveness options.

Understanding Common IRS Notices

• CP2000 Notice: Proposed adjustments to your return due to a mismatch between reported income and W-2/1099 data reported by third parties.
• Notice CP504 / LT11: Intent to levy assets due to unpaid balances. Requires immediate resolution or installment agreement request.
• Notice 5071C: Identity verification required before the IRS will process your tax return or issue refunds.

Penalty Relief Strategies

1. First-Time Penalty Abatement (FTA): If you have a clean compliance record for the past 3 tax years, you can request FTA to waive failure-to-file or failure-to-pay penalties under administrative IRS relief rules.

2. Reasonable Cause Abatement: Under IRC §6651, penalties can be abated if you establish that you exercised ordinary business care and prudence but were nevertheless unable to file or pay on time due to circumstances beyond your control (serious illness, natural disaster, destroyed records).