Self-employment income for child support.

Business owners, contractors and gig workers rarely have a single income figure. Guidelines generally start from gross receipts minus ordinary and necessary business expenses, but the expenses allowed for support can differ from the deductions allowed on a tax return.

Start with receipts and real business expenses

Louisiana’s guideline, for example, defines self-employment income as gross receipts minus ordinary and necessary expenses required to produce the income. Most states use a similar starting point. List the business’s gross receipts, then each category of expense, and keep the records that support both.

Tax deductions that support guidelines often add back

A business tax return is written to reduce taxable income. A support guideline is written to measure money available for the children. Items that commonly receive a second look include:

• Depreciation, especially accelerated or bonus depreciation, which can reduce taxable profit without reducing cash in the same year.
• Personal expenses paid by the business, such as a vehicle, phone or meals that also serve personal use.
• Home-office deductions that overlap with household costs.
• Retained earnings in a closely held company that the owner controls.

Whether each item is added back depends on the state guideline and the evidence. Keep a separate note for every adjustment you make.

Self-employment tax

Self-employed parents pay both halves of Social Security and Medicare tax. Many net-income states allow this tax as a deduction. Delaware’s Form 509 applies a specific deduction to documented self-employment earnings. Apply only what your state lists.

Avoid counting the same money twice

Business profit and an owner’s draw are often the same money described two ways. Do not add a distribution on top of the profit it came from. Likewise, a salary paid to the owner by their own corporation is already a business expense, so the profit figure should not include it again.

Fluctuating income

When earnings swing from year to year, courts commonly average several years rather than relying on a single strong or weak year. North Dakota’s guideline addresses fluctuating self-employment earnings specifically. Prepare at least three years of records so the averaging question can be answered from evidence.

Gig and platform work

Ride-share, delivery and freelance platforms issue 1099 forms that report gross payments. Platform fees, mileage and supplies may be deductible business expenses. Keep the platform’s annual summary, a mileage log and receipts, and treat tips as income.

Records to prepare

• Business and personal tax returns for three years, with all schedules.
• A year-to-date profit-and-loss statement and the prior year-end statement.
• Bank statements for business accounts.
• 1099s and platform annual summaries.
• A list of adjustments you made, with the reason for each.

Next: check which income definition your state uses, or read about imputed income.

Updated October 17, 2026. Published by Kestervale LLC. Educational information, not legal advice. Report a correction.