Contractor Taxes and Bookkeeping: The No-Nonsense Guide

Tax season surprises most new contractors. Not because the concepts are complicated — but because nobody warned them that self-employment taxes work completely differently from what they experienced as a W-2 employee. The result is a first-year tax bill that feels like getting hit from behind.

This guide lays out everything you need to know upfront: how self-employment tax works, what to set aside, when to pay, what you can deduct, and how to keep your books clean enough that tax time isn’t a crisis.

The Single Most Important Thing

Set aside 25 to 30 percent of every dollar of net profit the day it hits your account. Transfer it to a separate savings account. Do not touch it. That money belongs to the IRS and your state. Everything else in this guide builds on that foundation.


The Tax Reality for Self-Employed Contractors

When you worked a W-2 job, your employer handled half your Social Security and Medicare taxes, withheld federal and state income tax from every paycheck, and dealt with the IRS on your behalf. You received a paycheck and filed a return once a year.

As a self-employed contractor, all of that falls on you. There is no withholding. There is no employer covering half your payroll taxes. You owe the full 15.3 percent self-employment tax on top of income tax — and you’re expected to pay it quarterly, not annually.

What a $60,000 Net Profit Actually Costs in Taxes
Net profit$60,000
Self-employment tax (15.3% on 92.35% of net)~$8,478
SE tax deduction (saves ~50% of SE tax)-$4,239
Adjusted gross income~$51,761
Federal income tax (22% bracket est.)~$6,500
State income tax (varies — est. 5%)~$2,588
Total estimated tax liability~$13,227

That’s roughly 22 percent of net profit. Add higher state income tax rates or a higher federal bracket and you can hit 30 percent easily. Set aside conservatively.


Everything in This Hub

Self-Employment Tax Explained

The 15.3% tax most new contractors don’t see coming — how it works and how to calculate it.

Read the Guide →
Quarterly Estimated Taxes

When to pay, how much to pay, and how to avoid underpayment penalties.

Read the Guide →
The 20 Biggest Tax Deductions

Every legitimate deduction available to exterior home service contractors.

Read the Guide →
Mileage Tracking

The IRS standard mileage rate and how to track it correctly all year.

Read the Guide →
Simple Bookkeeping Setup

How to keep your books clean with free and cheap tools from day one.

Read the Guide →
Wave vs. QuickBooks vs. Spreadsheet

Which bookkeeping tool is right for your stage and trade.

Read the Guide →
How to Pay Yourself from Your LLC

Owner’s draws, distributions, and the right way to move money out.

Read the Guide →
1099 Rules

When you issue 1099s to subs and what happens if you don’t.

Read the Guide →
Sales Tax on Services

Which states tax lawn care, landscaping, and other exterior services.

Read the Guide →
Survive Your First Tax Season

What to expect and how to get through it without a crisis.

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Receipts and Record-Keeping

What to save, how long to save it, and how to organize it all.

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CPA vs. DIY Taxes

When it makes sense to hire a professional and what to look for.

Read the Guide →
The Bottom Line

Taxes are the biggest financial surprise new contractors face. The fix is simple: set aside 25 to 30 percent of net profit from day one, pay quarterly, track every deductible expense, and keep your books current. None of it is complicated — it just requires building the habits early before you’re scrambling to reconstruct a year’s worth of records in April.


Frequently Asked Questions

How much should I set aside for taxes as a contractor?

Set aside 25 to 30 percent of net profit. This covers self-employment tax at 15.3 percent plus federal and state income tax. If your state has no income tax, 20 to 25 percent is usually sufficient. Set it aside immediately when revenue hits your account — don’t wait until quarterly payment time.

When are quarterly estimated tax payments due?

April 15, June 15, September 15, and January 15 of the following year. Mark these in your calendar from day one. Missing a payment triggers an underpayment penalty from the IRS even if you pay everything owed by the annual filing deadline.

Do I need an accountant as a new contractor?

Not necessarily in year one if your income is straightforward and you’re diligent about tracking expenses. Many new contractors handle their own taxes using TurboTax Self-Employed or H&R Block. Once you have employees, significant equipment purchases, or complex deductions, a CPA typically pays for itself in tax savings and time.

Business Formation Hub  ·  Insurance & Bonding Hub  ·  Free Quarterly Tax Estimator  ·  Tax Deduction Tracker

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